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Keratoconus is a common ocular disorder that causes progressive corneal thinning and is the leading indication for corneal transplantation. Central corneal thickness (CCT) is a highly heritable characteristic that is associated with keratoconus. In this two-stage genome-wide association study (GWAS) of CCT, we identified a locus for CCT, namely STON2 rs2371597 (P = 2.32 × 10−13), and confirmed a significant association between STON2 rs2371597 and keratoconus development (P = 0.041). Additionally, strong STON2 expression was observed in mouse corneal epithelial basal cells. We also identified SMAD3 rs12913547 as a susceptibility locus for keratoconus development using predictive analysis with IBM’s Watson question answering computer system (P = 0.001). Further GWAS analyses combined with Watson could effectively reveal detailed pathways underlying keratoconus development., Yoshikatsu Hosoda et al. study the genetic basis for central corneal thickness (CCT) that is associated with keratoconus. They identify two susceptibility loci, STON2 rs2371597 and SMAD3 rs12913547, using two-step genome-wide association study (GWAS) and predictive analysis with IBM’s Watson question answering computer system, respectively.

The aim of this study was to determine whether early mobilization was associated with rehospitalization among elderly heart failure patients. We measured the time from admission to mobilization and other clinical characteristics for 190 heart failure patients (mean age, 80.7 years). The primary outcome was heart failure rehospitalization. Kaplan-Meier survival curves were plotted and the hazard ratios for rehospitalization were determined using Cox proportional hazards regression models. During a median follow-up period of 750 days, 58 patients underwent rehospitalization. The time from admission to mobilization was significantly longer for these patients than for those who were not rehospitalized. Univariate and multivariate Cox proportional hazards analyses showed that the time from admission to mobilization was an independent predictor of rehospitalization, and receiver-operating characteristic analysis determined an optimal cutoff value of 3 days for differentiating the patients more likely to experience a subsequent cardiac event (sensitivity, 76%; specificity, 69%; area under the curve, 0.667). Kaplan-Meier survival curve analysis showed a significantly lower event rate in the ≤ 3-day group (p = 0.001, log-rank test). In conclusion, the time from admission to mobilization may be one of the strongest predictors of rehospitalization in elderly heart failure patients. Early mobilization within 3 days may be an initial target for the acute phase treatment of heart failure.

Although cardiac sarcoidosis is associated with poor prognosis, diagnosis of the disease is challenging and the sensitivity and specificity of diagnostic modalities are limited. This study was performed to evaluate the potential of serum microRNAs (miRNAs) as diagnostic biomarkers for cardiac sarcoidosis.We performed genome-wide expression profiling for 2565 miRNAs (Human-miRNA ver.21) using peripheral blood samples from 5 patients with cardiac sarcoidosis (61±9 years) and 3 healthy controls (54±7 years). From this screening study, we selected 12 miRNAs that were significantly related to cardiac sarcoidosis. Next, we performed real-time polymerase chain reaction (PCR) on blood samples from 15 new patients with cardiac sarcoidosis and 4 healthy controls to quantify the expression of these 12 miRNAs.In the screening study, 12 miRNAs were differentially expressed (p0.01) in all 5 patients with cardiac sarcoidosis, showing greater fold-change values (4 or0.25) compared with the expression in the 3 healthy controls. Analysis of the real-time PCR for blood samples from the other 15 patients and 4 controls using Mann-Whitney U tests revealed that the expression of miR-126 and miR-223 was significantly higher in the patients than in the healthy individuals. However, there were no differences in the expressions of miRNA-126 and miR-223 between patients with only cardiac lesions and those with extra-cardiac lesions.Our results demonstrate the potential of serum miR-126 and miR-223 as new-generation biomarkers for the differential diagnosis of cardiac sarcoidosis in patients with heart failure.

Characteristics of high frequency (HF) component based on heart rate variability (HRV) in a large general population remain unclear, particularly on the relationship with daily physical activity. We aimed to characterize the distribution of HF component and examine the association with daily physical activity among community residents. We performed spectral analysis of HRV from 10-second ECG recordings among 9135 residents aged 30 to 74 years in Nagahama City, Japan. HF components were log-transformed to consider the distribution. Simple correlations between HF and age were determined. Age-adjusted mean values of HF component were calculated for each questionnaire item related to daily physical activity. Multiple regression analysis was performed to examine the effect of daily physical activity on HF component value. Mean values of logarithmically-transformed HF component (lnHF) were higher in women than in men (p < 0.001). lnHF was inversely associated with age (r = -0.40, -0.49 for men, women, respectively). Adjusted mean lnHF for physically active people was significantly higher than that in inactive people (p < 0.001). HF components from 10-second ECG recordings were moderately and negatively correlated with age in both sexes, and positively correlated with daily physical activity in the general adult population. Maintaining the level of daily physical activity, especially to exercise regularly could keep the parasympathetic function high.

The incidence of high myopia is increasing worldwide with myopic maculopathy, a complication of myopia, often progressing to blindness. Our two-stage genome-wide association study of myopic maculopathy identifies a susceptibility locus at rs11873439 in an intron of CCDC102B (P = 1.77 × 10−12 and Pcorr = 1.61 × 10−10). In contrast, this SNP is not significantly associated with myopia itself. The association between rs11873439 and myopic maculopathy is further confirmed in 2317 highly myopic patients (P = 2.40 × 10−6 and Pcorr = 1.72 × 10−4). CCDC102B is strongly expressed in the retinal pigment epithelium and choroids, where atrophic changes initially occur in myopic maculopathy. The development of myopic maculopathy thus likely exhibits a unique background apart from the development of myopia itself; elucidation of the roles of CCDC102B in myopic maculopathy development may thus provide insights into preventive methods for blindness in patients with high myopia., 強度近視の失明メカニズムに関わる遺伝子変異を発見 --失明予防法開発の第一歩--. 京都大学プレスリリース. 2018-05-14.

Genetic polymorphisms and sex differences are suggested to affect muscle fiber composition; however, no study has investigated the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences. Therefore, the present study examined the effects of genetic polymorphisms on muscle fiber composition with respect to sex differences in the Japanese population. The present study included 211 healthy Japanese individuals (102 men and 109 women). Muscle biopsies were obtained from the vastus lateralis to determine the proportion of myosin heavy chain (MHC) isoforms (MHC-I, MHC-IIa, and MHC-IIx). Moreover, we analyzed polymorphisms in α-actinin-3 gene ( ACTN3; rs1815739 ), angiotensin-converting enzyme gene ( ACE; rs4341 ), hypoxia-inducible factor 1 α gene ( rs11549465 ), vascular endothelial growth factor receptor 2 gene ( rs1870377 ), and angiotensin II receptor, type 2 gene ( rs11091046 ), by TaqMan single-nucleotide polymorphism genotyping assays. The proportion of MHC-I was 9.8% lower in men than in women, whereas the proportion of MHC-IIa and MHC-IIx was higher in men than in women (5.0 and 4.6%, respectively). Men with the ACTN3 RR + RX genotype had a 4.8% higher proportion of MHC-IIx than those with the ACTN3 XX genotype. Moreover, men with the ACE ID + DD genotype had a 4.7% higher proportion of MHC-I than those with the ACE II genotype. Furthermore, a combined genotype of ACTN3 R577X and ACE insertion/deletion (I/D) was significantly correlated with the proportion of MHC-I ( r = −0.23) and MHC-IIx ( r = 0.27) in men. In contrast, no significant correlation was observed between the examined polymorphisms and muscle fiber composition in women. These results suggest that the ACTN3 R577X and ACE I/D polymorphisms independently affect the proportion of human skeletal muscle fibers MHC-I and MHC-IIx in men but not in women.NEW & NOTEWORTHY In men, the RR + RX genotype of the α-actinin-3 gene ( ACTN3) R577X polymorphism was associated with a higher proportion of myosin heavy chain (MHC)-IIx. The ID + DD genotype of the angiotensin-converting enzyme gene ( ACE) insertion/deletion (I/D) polymorphism, in contrast to a previous finding, was associated with a higher proportion of MHC-I in men. In addition, the combined genotype of these polymorphisms was correlated with the proportion of MHC-I and MHC-IIx in men. Thus ACTN3 R577X and ACE I/D polymorphisms influence the muscle fiber composition in Japanese men.

Background It is well known that vascular endothelial growth factor (VEGF) inhibitors can cause proteinuria. The incidence of proteinuria is high for bevacizumab, a humanized monoclonal antibody directed against VEGF, but the range of proteinuria rarely becomes nephrotic (2.2% occurrence according to a meta-analysis). In such cases, renal pathology shows thrombotic microangiopathy (TMA). Ramucirumab, anti-VEGF receptor 2 (VEGFR2) monoclonal antibody, can also cause proteinuria, but it is not yet reported whether the drug may induce TMA. Case presentation Here, we report a case who immediately developed TMA by ramucirumab after multiple courses of bevacizumab treatment. This is the first case of pathologically-proved TMA by ramucirumab. After cessation of the drug, symptoms of TMA improved gradually. Conclusions This case demonstrates that not only blockade of VEGF but also VEGFR2 antagonism may result in TMA, which is a rare but life-threatening complication of cancer treatment drug.

The recently emerged pachychoroid concept has changed the understanding of age-related macular degeneration (AMD), which is a major cause of blindness; recent studies attributed AMD in part to pachychoroid disease central serous chorioretinopathy (CSC), suggesting the importance of elucidating the CSC pathogenesis. Our large genome-wide association study followed by validation studies in three independent Japanese and European cohorts, consisting of 1546 CSC samples and 13, 029 controls, identified two novel CSC susceptibility loci: TNFRSF10A-LOC389641 and near GATA5 (rs13278062, odds ratio = 1.35, P = 1.26 × 10−13; rs6061548, odds ratio = 1.63, P = 5.36 × 10−15). A T allele at TNFRSF10A-LOC389641 rs13278062, a risk allele for CSC, is known to be a risk allele for AMD. This study not only identified new susceptibility genes for CSC, but also improves the understanding of the pathogenesis of AMD., 特殊な網膜剥離の発症に関わる遺伝子変異を発見 --中心性漿液性脈絡網膜症のゲノムワイド関連解析--. 京都大学プレスリリース. 2019-12-13.

Human immune systems are very complex, and the basis for individual differences in immune phenotypes is largely unclear. One reason is that the phenotype of the immune system is so complex that it is very difficult to describe its features and quantify differences between samples. To identify the genetic factors that cause individual differences in whole lymphocyte profiles and their changes after vaccination without having to rely on biological assumptions, we performed a genome-wide association study (GWAS), using cytometry data. Here, we applied computational analysis to the cytometry data of 301 people before receiving an influenza vaccine, and 1, 7, and 90 days after the vaccination to extract the feature statistics of the lymphocyte profiles in a nonparametric and data-driven manner. We analyzed two types of cytometry data: measurements of six markers for B cell classification and seven markers for T cell classification. The coordinate values calculated by this method can be treated as feature statistics of the lymphocyte profile. Next, we examined the genetic basis of individual differences in human immune phenotypes with a GWAS for the feature statistics, and we newly identified seven significant and 36 suggestive single-nucleotide polymorphisms associated with the individual differences in lymphocyte profiles and their change after vaccination. This study provides a new workflow for performing combined analyses of cytometry data and other types of genomics data.

Allergic rhinitis, a known risk factor for asthma onset, often accompanies mouth breathing. Mouth breathing may bypass the protective function of the nose and is anecdotally considered to increase asthma morbidity. However, there is no epidemiological evidence that mouth breathing is independently associated with asthma morbidity and sensitization to allergens. In this study, we aimed to clarify the association between mouth breathing and asthma morbidity and allergic/eosinophilic inflammation, while considering the effect of allergic rhinitis. This community-based cohort study, the Nagahama Study, contained a self-reporting questionnaire on mouth breathing and medical history, blood tests, and pulmonary function testing. We enrolled 9804 general citizens of Nagahama City in the Shiga Prefecture, Japan. Mouth breathing was reported by 17% of the population and was independently associated with asthma morbidity. The odds ratio for asthma morbidity was 1.85 (95% confidence interval, 1.27-2.62) and 2.20 (95% confidence interval, 1.72-2.80) in subjects with mouth breathing alone and allergic rhinitis alone, which additively increased to 4.09 (95% confidence interval, 3.01-5.52) when mouth breathing and allergic rhinitis co-existed. Mouth breathing in non-asthmatics was a risk for house dust mite sensitization, higher blood eosinophil counts, and lower pulmonary function after adjusting for allergic rhinitis. Mouth breathing may increase asthma morbidity, potentially through increased sensitization to inhaled allergens, which highlights the risk of mouth-bypass breathing in the "one airway, one disease" concept. The risk of mouth breathing should be well recognized in subjects with allergic rhinitis and in the general population. This article is protected by copyright. All rights reserved.

[Background]Previous studies have reported that artificial increases in circulating free fatty acid (FFA) levels might have adverse effects on the vasculature. However, whether or not this effect can be extrapolated to physiological variations in FFA levels has not been clarified. Given that FFAs exert a lipotoxic effect on pancreatic β-cells and might directly damage the arterial endothelium, we hypothesized that these adverse effects might synergize with hyperglycemia. [Methods] A total of 9396 Japanese subjects were included in the study. Serum FFA levels were measured at baseline examination. Brachial-to-ankle pulse wave velocity (baPWV) was measured as an index of arterial stiffness. [Results] As serum levels of FFA were markedly lower in subjects with higher insulin level, a significant association between FFA levels and baPWV was observed only in subjects with blood samples taken under fasting (≥ 12 h, P < 0.001) or near-fasting (5–11 h, P < 0.001) conditions, and not in those taken under non-fasting (< 5 h, P = 0.307) conditions. Although type 2 diabetes and HbA1c showed a strong association with baPWV, the association between FFA level and baPWV remained significant (β = 0.052, P < 0.001) after adjustment for glycemic levels. In addition to their direct relationship, FFA and glucose levels were synergistically associated with baPWV (FFA⁎glucose; β = 0.036, P < 0.001). Differences in baPWV between the lowest and highest subgroups divided by a combination of FFA and glucose reached approximately 300 cm/s. [Conclusions] Physiological variations in FFA concentrations might be a risk factor for large arterial stiffness. FFA and hyperglycemia exert a synergistic adverse effect on the vasculature.

The main symptom of Parkinson's disease (PD) is motor dysfunction and remarkably approximately 30–40% of PD patients exhibit cognitive impairments. Recently, we have developed MF8, a heart-type fatty acid-binding protein (FABP3)-specific ligand, which can inhibit α-synuclein (α-syn) oligomerization induced by arachidonic acid in FABP3 overexpressing neuro2A cells. The present study aimed to determine whether MF8 attenuates dopaminergic neuronal death and motor and cognitive impairments in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced PD mice model. MF8 can penetrate the blood-brain barrier and its peak brain concentration (21.5 ± 2.1 nM) was achieved 6 h after the oral administration (1.0 mg/kg). We also compared its effects and pharmacological action with those of L-DOPA (3,4-dihydroxy-l-phenylalanine). PD model mice were developed by administering MPTP (25 mg/kg, i.p.) once a day for five consecutive days. Twenty-four hours after the final MPTP injection, mice were administered MF8 (0.3, 1.0 mg/kg, p.o.) or L-DOPA (25 mg/kg, i.p.) once a day for 28 consecutive days and subjected to behavioral and histochemical studies. MF8 (1.0 mg/kg, p.o.), but not L-DOPA, inhibited the dopaminergic neuronal death in the ventral tegmental area and the substantia nigra pars compacta region of the MPTP-treated mice. MF8 also improved both, motor and cognitive functions, while L-DOPA ameliorated only motor dysfunction. Taken together, our results showed that MF8 attenuated the MPTP-induced dopaminergic neuronal death associated with PD pathology. We present MF8 as a novel disease-modifying therapeutic molecule for PD, which acts via a mechanism different from that of L-DOPA.

To assess the use of plasma free amino acids (PFAAs) as biomarkers for metabolic disorders, it is essential to identify genetic factors that influence PFAA concentrations. PFAA concentrations were absolutely quantified by liquid chromatography–mass spectrometry using plasma samples from 1338 Japanese individuals, and genome-wide quantitative trait locus (QTL) analysis was performed for the concentrations of 21 PFAAs. We next conducted a conditional QTL analysis using the concentration of each PFAA adjusted by the other 20 PFAAs as covariates to elucidate genetic determinants that influence PFAA concentrations. We identified eight genes that showed a significant association with PFAA concentrations, of which two, SLC7A2 and PKD1L2, were identified. SLC7A2 was associated with the plasma levels of arginine and ornithine, and PKD1L2 with the level of glycine. The significant associations of these two genes were revealed in the conditional QTL analysis, but a significant association between serine and the CPS1 gene disappeared when glycine was used as a covariate. We demonstrated that conditional QTL analysis is useful for determining the metabolic pathways predominantly used for PFAA metabolism. Our findings will help elucidate the physiological roles of genetic components that control the metabolism of amino acids.

Anti-citrullinated peptide antibody (ACPA) is a highly specific autoantibody to rheumatoid arthritis (RA). Recent studies have revealed that periodontal disease (PD) is closely associated with RA and production of ACPA in RA. Analyses of associations between PD and ACPA production in a healthy population may deepen our understandings. Here, we analyzed a total of 9554 adult healthy subjects. ACPA and IgM-rheumatoid factor (RF) was quantified and PD status was evaluated using the number of missing teeth (MT), the Community Periodontal Index (CPI) and Loss of Attachment (LA) for these subjects. PD status was analyzed for its association with the positivity and categorical levels of ACPA and RF conditioned for covariates which were shown to be associated with PD, ACPA or RF. As a result, all of MT, CPI and LA showed suggestive or significant associations with positivity (p=0.024, 0.0042 and 0.037, respectively) and levels of ACPA (p≤0.00031), but none of the PD parameters were associated with those of RF. These association patterns were also observed when we analyzed 6206 non-smokers of the participants. The significant associations between PD parameters and positivity and levels of ACPA in healthy population support the fundamental involvement of PD with ACPA production., 歯周病と関節リウマチ発症との相関を示す. 京都大学プレスリリース. 2015-04-21.

Although central blood pressure (BP) is considered to be more closely associated with large arterial remodeling and cardiovascular outcomes than brachial BP, few studies have investigated these associations with changes in small arteries. As morphological changes in retinal vessels might be associated with cardiovascular outcomes, we conducted a cross-sectional study to investigate the association of central BP with retinal vessel caliber.The study included 8054 Japanese participants. Central BP was estimated by the radial arterial waveform by calibrating brachial BP. Central retinal arteriolar equivalent (CRAE) was computationally measured using fundus photography.CRAE was most strongly associated with central SBP (r = -0.324, P 0.001), followed by DBP (r = -0.292, P 0.001) and central pulse pressure (PP; r = -0.226, P 0.001). The correlation coefficient between SBP and CRAE was significantly greater in central SBP than in brachial SBP (r = -0.300, P 0.001). After adjustment for possible covariates, brachial SBP (β = -0.221, P 0.001) and central SBP (β = -0.239, P 0.001) were independently associated with CRAE. Further, higher brachial SBP (β = -0.226, P 0.001) and smaller PP amplification (β = 0.092, P 0.001) were identified as independent determinants of narrowing of CRAE in the same equation, which indicated the superiority of central BP. Central BP-determined hypertensive individuals had a significantly narrower CRAE independent of brachial BP (central/brachial: hypertension/hypertension 121.4 ± 11.5, hypertension/normotension 120.9 ± 11.2, normotension/hypertension 125.1 ± 11.9, normotension/normotension 128.1 ± 11.5 μm).Central BP was more closely associated with the narrowing of CRAE than brachial BP. Slight increases in central BP might be involved in the morphological changes in small retinal arteries, even in individuals with optimal brachial BP.

The prevalence of overactive bladder is increasing globally. It has a substantial impact on quality of life and represents a heavy economic burden. We evaluated the prevalence of overactive bladder in a Japanese population and analyzed whether genetic and environmental factors influence overactive bladder.This cross-sectional study was performed as part of the Nagahama cohort project. It comprised a questionnaire survey as well as anthropometric, physiological and biochemical measures, and genomic information on participants 30 to 74 years old in Nagahama, Japan. A genome-wide association study was performed in 4,645 participants, including 1,521 men and 3,124 women, using 99,059 single nucleotide polymorphisms. Univariate and multivariable logistic regression was done to analyze environmental factors associated with overactive bladder.The prevalence of overactive bladder was 11.8%, including 15.3% in men and 10.1% in women, and it increased with age. We found no significant association between overactive bladder and any single nucleotide polymorphism in the genome-wide association study. However, in the multivariable logistic regression model overactive bladder was positively associated with environmental factors, including age, depression and the consumption of cake or Japanese confection.The prevalence of overactive bladder was greater in men than in women, especially among the elderly. Environmental factors rather than genetic variants more likely contribute to overactive bladder.

We conducted a genome-wide association study (GWAS) on the outcome of anti-VEGF treatment for exudative age-related macular degeneration (AMD) in a prospective cohort. Four hundred and sixty-one treatment-naïve AMD patients were recruited at 13 clinical centers and all patients were treated with 3 monthly injections of ranibizumab followed by pro re nata regimen treatment for one year. Genomic DNA was collected from all patients for a 2-stage GWAS on achieving dry macula after the initial treatment, the requirement for an additional treatment, and visual acuity changes during the 12-month observation period. In addition, we evaluated 9 single-nucleotide polymorphisms (SNPs) in 8 previously reported AMD-related genes for their associations with treatment outcome. The discovery stage with 256 patients evaluated 8,480,849 SNPs, but no SNPs showed genome-wide level significance in association with treatment outcomes. Although SNPs with P-values of −6 were evaluated in replication samples of 205 patients, no SNP was significantly associated with treatment outcomes. Among AMD-susceptibility genes, rs10490924 in ARMS2/HTRA1 was significantly associated with additional treatment requirement in the discovery stage (P = 0.0023), and pooled analysis with the replication stage further confirmed this association (P = 0.0013). ARMS2/HTRA1 polymorphism might be able to predict the frequency of injection after initial ranibizumab treatment.

Background Pulmonary arterial hypertension (PAH) is a severe lung disease with only few effective treatments available. Familial cases of PAH are usually recognized as an autosomal dominant disease, but incomplete penetrance of the disease makes it difficult to identify pathogenic variants in accordance with a Mendelian pattern of inheritance. Methods To elucidate the complex genetic basis of PAH, we obtained whole exome- or genome-sequencing data of 17 subjects from 9 families with heritable PAH and applied gene-based association analysis with 9 index patients and 300 PAH-free controls. Results A burden of rare variants in BMPR2 significantly contributed to the risk of the disease (p = 6.0 × 10−8). Eight of nine families carried four previously reported single nucleotide variants and four novel insertion/deletion variants in the gene. One of the novel variants was a large 6.5 kilobase-deletion. In the remaining one family, the patient carried a pathogenic variant in a member of potassium channels, KCNK3, which was the first replicative finding of channelopathy in an Asian population. Conclusions The variety of rare pathogenic variants suggests that gene-based association analysis using genome-wide sequencing data from increased number of samples is essential to tracing the genetic heterogeneity and developing an appropriate panel for genetic testing. Electronic supplementary material The online version of this article (doi:10.1186/s12890-017-0400-z) contains supplementary material, which is available to authorized users.

Background:Non-restorative sleep (NRS) was suggested to be associated with cardiovascular outcomes. However, causative factors for NRS have not been fully elucidated. This study aimed to clarify factors and their relationships with NRS to better understand the clinical and epidemiological implications of NRS and to develop a score that can objectively evaluate NRS status., Methods:Study subjects consisted of 9,788 community residents (age 53.6 ± 13.4 y). Subjective NRS as well as possible clinical and lifestyle factors for NRS were investigated by questionnaires. Other clinical parameters were obtained from personal records of information obtained at the baseline examination., Results:A total of 3,261 participants complained of NRS. Factors independently associated with subjective NRS were younger age (odds ratio = 1.43), use of a hypnotic drug (2.04), irregular sleep schedule (2.02), short sleep duration (, Conclusions:NRS was a phenomenon representing various clinical and lifestyle features. Careful attention should be paid to individuals with a high NRS score who might be at risk for mental fatigue and have unfavorable lifestyle factors.

STUDY OBJECTIVES To examine relationships among gastroesophageal reflux disease (GERD) symptoms, dietary behaviors, and sleep duration in the general population. DESIGN Cross-sectional. SETTING Community-based. PARTICIPANTS There were 9,643 participants selected from the general population (54 ± 13 y). INTERVENTIONS None. MEASUREMENTS AND RESULTS Sleep duration, sleep habits, and unfavorable dietary behaviors of each participant were assessed with a structured questionnaire. Participants were categorized into five groups according to their sleep duration: less than 5 h, 5 to less than 6 h, 6 to less than 7 h, 7 to less than 8 h, and 8 or more h per day. GERD was evaluated using the Frequency Scale for the Symptoms of GERD (FSSG) and participants having an FSSG score of 8 or more or those under treatment of GERD were defined as having GERD. Trend analysis showed that both the FSSG score and the number of unfavorable dietary habits increased with decreasing sleep duration. Further, multiple logistic regression analysis showed that both the presence of GERD (odds ratio = 1.19, 95% confidence interval (CI) = 1.07-1.32) and the number of unfavorable dietary behaviors (odds ratio = 1.19, 95% CI = 1.13-1.26) were independent and potent factors to identify participants with short sleep duration even after controlling for other confounding factors. CONCLUSION The current study showed that both GERD symptoms and unfavorable dietary behaviors were significant correlates of short sleep duration independently of each other in a large sample from the general population.

Background Prostate-specific antigen (PSA) is a useful marker for prostate cancer (PCa) and is widely used for screening of PCa. Previous studies have shown that genetic components influence the levels of PSA, and some of these genetic components would lead to better diagnostic sensitivity and specificity to PCa. However, genetic studies for PSA from Asian countries are limited. Our aim was to identify genetic components influencing PSA levels in the Japanese population using genome-wide association study (GWAS) and to analyse whether genetic components would lead to better screening abilities of PCa. Methods We performed a GWAS comprising 1086 male subjects using 303 283 single nucleotide proteins, followed by a replication study of 1302 subjects. PSA levels were quantified by chemiluminescence immunoassay method. Quantitative linear regression analysis was performed to assess genetic components of PSA levels. A total of 413 subjects with prostate biopsies were analysed to examine whether genetic determinants would improve diagnostic ability. Results Rs16856139 in SLC45A3 , the same region as the previous Chinese study, showed an overall significant association with PSA levels (p=2.4×10−11) along with rs1058205 in KLK3 . In silico analysis revealed significant association between rs16856139 and expression of SLC45A3 . Genetic scores of PSA showed a dose-dependent decrease of area under curve (AUC) of PCa and successfully subgrouped the individuals with significantly different AUC (p≤0.0097). Conclusions Rs16856139, associated with the expression of SLC45A3 , is significantly associated with the levels of PSA in the Japanese population. Classification of subjects based on PSA genetic determinants would improve screening ability of PSA to detect PCa.

Pathophysiological mechanisms of associations between airflow limitation (AL) and arterial stiffness remain unclear. One factor that might affect both AL and arterial stiffness is habitual smoking. The aim of this study is to investigate a possible interaction of smoking on the association between AL and arterial stiffness.Study subjects consisted of 8790 apparently healthy community residents. Airflow limitation was defined as a ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity of less than 70%. Brachial-to-ankle pulse wave velocity (baPWV) was used as an index of arterial stiffness. Smoking habit was investigated using a structured questionnaire.Subjects with AL had significantly higher baPWV (AL 1381 ± 334, control 1261 ± 227 cm/s, p0.001). In a separate analysis by smoking habit, advanced arterial stiffness in AL was observed only in smokers (non-smokers: AL 1300 ± 220, control 1260 ± 218; smokers: AL 1436 ± 384, control 1264 ± 243 cm/s). Other clinical features of subjects with AL were older age; increased plasma hsCRP levels; and a high prevalence of male sex, hypertension, and smoking experience. Multiple linear regression analysis adjusted for these covariates identified the smoking × AL interaction as an independent determinant of baPWV (β = 0.066, p0.001). Conversely, baPWV was an independent determinant of AL in current and past smokers, but not in never smokers.AL arising from cigarette smoking, but not AL in non-smokers, was associated with arterial stiffness in a general population independently of established risk factors. Measurement of subclinical arterial change in smokers may be useful in identifying persons at risk for AL.

[Background]Central blood pressure (cSBP) is suggested to be a better predictor of cardiovascular risk than brachial BP. Although brachial BP levels among smokers have been reported to be the same or somewhat lower than those in nonsmokers, it is suggested that smoking might have a substantial impact on cSBP. [Methods]We conducted a cross-sectional study to clarify the association of smoking habit with arterial tone and cSBP in a general population of 8557 participants using urinary cotinine levels as an objective marker of smoking intensity. Absolute pressure of the late systolic peak (SBP2) was obtained by calibrating the radial waveform with brachial systolic BP (bSBP) and considered to be the cSBP. [Results]Confounding factor-adjusted mean pulse pressure amplification (PPa = bSBP − cSBP) was significantly smaller in habitual smokers (current, 9.3 ± 0.15; past, 10.2 ± 0.13; never, 10.6 ± 0.10 mm Hg; p < 0.001). Further, among smokers, PPa was linearly decreased with increasing urinary cotinine quartile (Q1, 10.9 ± 0.38; Q2, 10.9 ± 0.39; Q3, 10.4 ± 0.39; Q4, 9.7 ± 0.41 mm Hg; p = 0.020). Multiple linear regression analysis identified both smoking habit (p = 0.003) and urinary cotinine levels (p = 0.008) as independent determinants of PPa. Urinary cotinine was also detected in a small fraction of never smokers (1.8%). These passive smokers showed a smaller PPa (passive smoker, 9.4 ± 0.4; never smoker, 10.4 ± 0.12 mm Hg, p = 0.020) but not bSBP (122.7 ± 0.6, 123.1 ± 0.2 mm Hg, p = 0.474). [Conclusions]Not only habitual smoking but also passive smoking had harmful effects on AIx and central BP. Our results strongly emphasize the importance of avoiding passive smoking to the prevention of cardiovascular risks of which the subject is likely unaware.

Objective Systemic sclerosis (SSc) is an autoimmune disease for which multiple susceptibility genes have been reported. Genome-wide association studies have shown that large numbers of susceptibility genes are shared among autoimmune diseases. Recently, our group identified 9 novel susceptibility genes associated with rheumatoid arthritis (RA) in a Japanese population. The aim of this study was to elucidate whether the 18 genes that displayed associations or suggestive associations for RA in our previous study are associated with SSc in Japanese. Methods We performed an association study that included 415 patients with SSc and 16,891 control subjects, followed by a replication study that included 315 patients and 21,054 control subjects. The 18 markers reported to display association with RA were analyzed for their associations with SSc in the first study, and 5 markers were further analyzed in the replication study. The inverse variance method was used to evaluate the associations of these markers with SSc in a combined study. Results In the phospholipase D4 gene (PLD4), rs2841277 displayed a significant association with SSc in Japanese patients (P = 0.00017). We observed that rs2841280 in exon 2 of PLD4 was in strong linkage disequilibrium with rs2841277 and introduced an amino acid alteration. We also observed associations between SSc and rs6932056 in TNFAIP3 and rs2280381 in IRF8 (P = 0.0000095 and P = 0.0030, respectively), both of which displayed associations with SSc in a European population. Conclusion We determined that PLD4 is a novel susceptibility gene for SSc in Japanese, thus confirming the involvement of PLD4 in autoimmunity. Associations between SSc and TNFAIP3 or IRF8 were also detected in our Japanese population. SSc and RA appear to share relatively large proportions of their genetic backgrounds.

Recent evidence suggests that a substantial portion of complex disease risk alleles modify gene expression in a cell-specific manner. To identify candidate causal genes and biological pathways of immune-related complex diseases, we conducted expression quantitative trait loci (eQTL) analysis on five subsets of immune cells (CD4+ T cells, CD8+ T cells, B cells, natural killer (NK) cells and monocytes) and unfractionated peripheral blood from 105 healthy Japanese volunteers. We developed a three-step analytical pipeline comprising (i) prediction of individual gene expression using our eQTL database and public epigenomic data, (ii) gene-level association analysis and (iii) prediction of cell-specific pathway activity by integrating the direction of eQTL effects. By applying this pipeline to rheumatoid arthritis data sets, we identified candidate causal genes and a cytokine pathway (upregulation of tumor necrosis factor (TNF) in CD4+ T cells). Our approach is an efficient way to characterize the polygenic contributions and potential biological mechanisms of complex diseases.

Chronic obstructive pulmonary disease (COPD) is a possible risk factor for cardiovascular disease. The association of COPD with the pathogenicity of infection with Chlamydia pneumoniae and Mycoplasma pneumoniae is controversial. We conducted a cross-sectional study to clarify the association between atypical pneumoniae seropositivity and COPD in a general population. We also investigated genetic polymorphisms conferring susceptibility to a pneumonia titer. The study included 9040 Japanese subjects (54 ± 13 years). COPD was defined as a ratio of forced expiratory volume in 1 second to forced vital capacity of less than 70%. Serum levels of IgA and IgG antibodies to C pneumoniae were determined using an enzyme-linked immunoassay, and M pneumoniae seropositivity was assessed by a particle agglutination test. Subjects seropositive for C pneumoniae (26.1%) had a higher prevalence of COPD (seropositive, 5.8%; seronegative, 3.1%; P

Resistin is a cytokine inducing insulin resistance in mice. We previously identified single nucleotide polymorphisms (SNPs) at −420 (rs1862513) and −358 (rs3219175) located in the human resistin gene ( RETN) promoter as strong determinants for circulating resistin in the Japanese population. The objective was to identify additional functional variants for circulating resistin. We conducted a genome-wide association study in 448 Japanese subjects. A peak association signal was found on chromosome 19 where RETN is located. The top-hit SNP was SNP −358 G>A, followed by rs1423096 C>T, SNP −420 C>G, and rs10401670 C>T ( P = 5.39×10−47, 1.81×10−22, 2.09×10−16, and 9.25×10−15, respectively). Meta-analysis including another two independent general Japanese populations showed that circulating resistin was most strongly associated with SNP-358, followed by SNP-420, rs1423096, and rs10401670. Rs1423096 and rs10401670 were located in the 3′-region of RETN and were in strong linkage disequilibrium. Although these SNPs were also in linkage disequilibrium with the promoter SNPs, conditional and haplotype association analyses identified rs1423096 and rs10401670 as independent determinants for circulating resistin. Functionally, nuclear proteins specifically recognized T but not C at rs10401670 as evidenced by an electrophoretic mobility shift assay. The promoter activity of a luciferase reporter with T at either rs1423096 or rs10401670 was lower than that with C in THP-1 human monocytes. Therefore, rs1423096 and rs10401670, in addition to SNP-420 and SNP-358, were identified as possible functional variants affecting circulating resistin by the genome-wide search in the Japanese population.

Rheumatoid arthritis (RA) is the most common immune-related inflammatory arthritis affecting 0.5-1.0% of the population. Both genetic and environmental factors are associated with RA onset. Twin studies reported from European countries estimated heritability of RA as 53-65%. However, no twin studies have been reported from Asian countries.We collected a total of 43 monozygotic and 43 dizygotic twins from 7550 patients with RA and obtained information of RA status in the twin pairs. We characterized RA patients whose twin siblings had RA. Variance components analysis was performed to estimate heritability in RA in the Japanese population.Four and one patients with RA over 43 monozygotic (9.3%) and 43 dizygotic twins (2.3%), respectively, had twin siblings with RA. All the patients whose information of sero-positivity was available and whose twin siblings had RA were sero-positive. Heritability of RA was estimated as 62.2% and 56.1% in the AE and ACE models, respectively. The estimated heritability was comparable with those reported in the Europeans, compatible with previous overlap of RA susceptibility genes between Japanese and European populations.Heritability of RA onset in the Japanese population is estimated to be comparable with that in European populations.

Background HLA-DRB1 is associated with rheumatoid arthritis (RA). However, it has recently been suggested that HLA-DRB1 is only associated with patients with RA who have anticitrullinated peptide/protein antibodies (ACPA), which are specific to RA. Objective To elucidate whether specific HLA-DR alleles are associated with ACPA-negative RA development. Methods HLA-DRB1 typing was carried out in 368 Japanese ACPA-negative patients with RA and 1508 healthy volunteers as the first set, followed by HLA-DRB1 typing of 501 cases and 500 controls as the second set. The HLA-DRB1 allele frequency and diplotype frequency were compared in each group, and the results of the two studies were combined to detect HLA-DRB1 alleles or diplotypes associated with ACPA-negative RA. Results HLA-DRB1*12:01 was identified as a novel susceptibility allele for ACPA-negative RA (p = 0.000088, OR=1.72, 95% CI 1.31 to 2.26). HLA-DRB1*04:05 and *14:03 showed moderate associations with ACPA-negative RA (p = 0.0063, OR=1.26, 95% CI 1.07 to 1.49 and p = 0.0043, OR=1.81, 95% CI 1.20 to 2.73, respectively). The shared epitope was weakly associated with ACPA-negative RA, but no dosage effect was detected (p = 0.016, OR=1.17, 95% CI 1.03 to 1.34). A combination of HLA-DRB1*12:01 and DRB1*09:01 showed a strong association with susceptibility to ACPA-negative RA (p = 0.00013, OR=3.62, 95% CI 1.79 to 7.30). Homozygosity for HLA-DR8 was significantly associated with ACPA-negative RA (p = 0.0070, OR=2.16, 95% CI 1.22 to 3.82). It was also found that HLA-DRB1*15:02 and *13:02 were protective against ACPA-negative RA (p = 0.00010, OR=0.68, 95% CI 0.56 to 0.83 and p = 0.00059, OR=0.66, 95% CI 0.52 to 0.84, respectively). Conclusions In this large-scale association study multiple alleles and diplotypes were found to be associated with susceptibility to, or protection against, ACPA-negative RA.

Urinary bladder cancer (UBC) is a common cancer with male predominance. Pathologically it is classified into two distinct tumor entities related to the risk of patients. The low-grade tumors with relatively well-differentiated tumor histology (G1 and G2) at stage Ta are non-invasive and pose a minimal risk, whereas high-grade tumors (G2 and G3) with stages T1 to T4 are aggressive with invasion, and therefore, pose a serious risk for the patients. DNA repair and metabolic process genes may have major roles in cancer progression and development. To identify genes associated with invasiveness of UBC, we have extensively genotyped 802 single nucleotide polymorphisms in 114 genes related to DNA repair mechanisms and metabolic processes. A genetic association study was performed between non-invasive (G1 and G2 with Ta) and invasive (G2 and G3 with T1 to T4) groups of Japanese UBC patients. We found that rs17650301 in POLG2 showed marked difference in genotype distribution between the two groups in males (P=6.93 × 10(-4)), which was further confirmed in an independent sample set (overall P=1.67 × 10(-4)). We also found by an in silico analysis that the risk allele of rs17650301 increased the transcription of POLG2. In conclusion, rs17650301 is a good candidate marker for UBC invasiveness in Japanese males.

Background FOXE1 and NKX2-1 are two known genetic risk factors for the predisposition to sporadic papillary thyroid carcinoma (PTC) in Europeans, but their association in other ethnicities is still unknown. Objective We aim to examine the association of the two genes with Japanese sporadic PTC, which exhibits high BRAF(V600E) mutation rate. Methods 507 Japanese sporadic PTC cases and 2766 controls were genotyped for rs965513 (FOXE1) and rs944289 (NKX2-1). PTC cases were also examined for their BRAF(V600E) mutational status. Results The association of both rs965513 (p=1.27×10(-4), OR=1.69, 95% CI 1.29 to 2.21) and rs944289 (p=0.0121, OR=1.21, 95% CI 1.04 to 1.39) with the risk of sporadic PTC was confirmed. Subgroup analysis based on the BRAF mutational status showed strong association of rs965513 with BRAF(V600E)-positive cases (p=2.26×10(-4), OR=1.72, 95% CI 1.29 to 2.29), but not with BRAF(V600E)-negative cases (p=0.143, OR=1.52, 95% CI 0.87 to 2.65). However, there was no difference in the observed effect size between both subgroups. For rs944289, both subgroups showed marginal association (p=0.0585, OR=1.17, 95% CI 0.99 to 1.37 for BRAF(V600E)-positive cases; p=0.0492, OR=1.35, 95% CI 1.00 to 1.81 for BRAF(V600E)-negative cases). Conclusions Both FOXE1 and NKX2-1 were associated with the increased risk of sporadic Japanese PTC. No clear associations were observed for either SNP with BRAF(V600E) status., Journal of Medical Genetics, 48(9), pp.645-648; 2011

Background and aim Colorectal cancer (CRC) is a multifactorial disease with both environmental and genetic factors contributing to its development. The incidence of CRC is increasing year by year in Japan. Patients with CRC in advanced stages have a poor prognosis, but detection of CRC at earlier stages can improve clinical outcome. Therefore, identification of epidemiologial factors that influence development of CRC would facilitate the prevention or early detection of disease. Methods To identify loci associated with CRC risk, we performed a genome-wide association study (GWAS) for CRC and sub-analyses by tumour location using 1583 Japanese CRC cases and 1898 controls. Subsequently, we conducted replication analyses using a total of 4809 CRC cases and 2973 controls including 225 Korean subjects with distal colon cancer and 377 controls. Results We identified a novel locus on 6q26-q27 region (rs7758229 in SLC22A3 , p=7.92×10 −9 , OR of 1.28) that was significantly associated with distal colon cancer. We also replicated the association between CRC and SNPs on 8q24 (rs6983267 and rs7837328, p=1.51×10 −8 and 7.44×10 −8 , ORs of 1.18 and 1.17, respectively). Moreover, we found cumulative effects of three genetic factors (rs7758229, rs6983267, and rs4939827 in SMAD7 ) and one environmental factor (alcohol drinking) which appear to increase CRC risk approximately twofold. Conclusions We found a novel susceptible locus in SLC22A3 that contributes to the risk of distal colon cancer in an Asian population. These findings would further extend our understanding of the role of common genetic variants in the aetiology of CRC.

Objective To examine the risk of anti–cyclic citrullinated peptide (anti-CCP) antibody positivity in rheumatoid arthritis (RA) patients carrying certain haplotypes in the HLA region. Methods A total of 1,389 Japanese patients with RA were genotyped for 30 single-nucleotide polymorphisms (SNPs) in the HLA region using commercial oligonucleotide arrays (from Perlegen or Affymetrix) as well as for HLA–DRB1 alleles using a sequence-specific polymerase chain reaction method. Stepwise logistic regression was used to select from among the 30 SNPs the ones that represented a risk of anti-CCP antibody positivity. Haplotypes of the selected SNPs were inferred using an expectation-maximization algorithm. Associations of individual SNPs were evaluated with the Cochran-Armitage test for trend. DRB1 alleles and haplotypes were evaluated with the chi-square test. Heterogeneities of risks among the shared epitope (SE) and non-SE HLA–DRB1 alleles were examined using the exact test. Haplotype associations that were independent of individual HLA–DRB1 alleles were evaluated using the likelihood ratio test. Results Significant associations were found for 9 SNPs (smallest P value being 2.4 × 10−8) and in 4 HLA–DRB1 alleles (smallest P value being 2.0 × 10−10 in DRB1*0405). Stepwise logistic regression selected 4 SNPs (rs9262638, rs7775228, rs4713580, and rs9277359). Among the 16 inferred haplotypes of these 4 SNPs, 6 indicated significant associations (smallest P value being 1.9 × 10−11). Risks among SE and non-SE alleles were significantly heterogeneous (P = 0.0095 and P = 9.8 × 10−9, respectively), indicating the importance of stratification with individual DRB1 alleles rather than SE alleles. Conditional analysis of the risk associated with individual DRB1 alleles identified a risk haplotype that was independent of DRB1 (odds ratio 2.00 [95% confidence interval 1.44–2.79], P = 2.6 × 10−5). Conclusion Heterogeneous risks of anti-CCP antibody positivity were confirmed among SE and non-SE alleles in our patient population. A risk haplotype in the HLA region that is independent of HLA–DRB1 was confirmed.

The purpose of this study was to investigate whether the genetic risk factors of age-related macular degeneration (AMD) are associated with the development of choroidal neovascularization (CNV) in highly myopic eyes of elderly Japanese.Highly myopic elderly Japanese patients with and without CNV were genotyped for three AMD-associated single nucleotide polymorphisms (SNPs), namely rs10490924 (A69S) of ARMS2, rs11200638 of HTRA1, and rs1061170 (Y402H) of complement factor H (CFH), with the TaqMan SNP assay. One hundred and eighty-three unrelated highly myopic (axial lengths26.00 mm or refractive errors-6.0 diopters) Japanese patients with CNV who wereor=50 years of age (mean age+/-standard deviation of 62.7+/-6.3 years) and 170 highly myopic patients without CNV who wereor=50 years old (62.3+/-7.1 years) were studied. The differences in the genotypic distributions for the three SNPs between the two groups were tested with the Trend chi2 test, and logistic regression analyses were performed for age and gender adjustment.No significant difference was detected in the distribution of the three SNPs, rs10490924 (P0.1), rs11200638 (P0.1), and rs1061170 (P0.5), between the two groups even after adjustments for age and gender differences.The genetic risk factors of AMD related to these SNPs do not contribute significantly to the development of CNV in a highly myopic elderly Japanese population.

Introduction:Association of knee and low back pain with sleep disturbance is poorly understood. We aimed to clarify the independent and combined effects of these orthopedic symptoms on sleep in a large-scale general population., Methods:Cross-sectional data about sleep and knee/low back pain were collected for 9,611 community residents (53±14 years old) by a structured questionnaire. Sleep duration less than 6 h/d was defined as short sleep. Sleep quality and the presence of knee and low back pain were evaluated by dichotomous questions. Subjects who complained about knee or low back pains were graded by tertiles of a numerical response scale (NRS) score and a Roland-Morris disability questionnaire (RDQ) score respectively. Multivariate regression analyses were performed to determine the correlates of short sleep duration and poor sleep quality., Results:Frequency of participants who complained of the orthopedic symptoms was as follows; knee pain, 29.0%; low back pain, 42.0% and both knee and low back pain 17.6%. Both knee and low back pain were significantly and independently associated with short sleep duration (knee pain: odds ratio (OR) = 1.19, p, Conclusion:Knee and low back pains were independently associated with short sleep duration and poor sleep quality. Further, they additively increased the correlation with these sleep problems in the general population.

[Objectives]: We undertook descriptive epidemiology of spot urine sodium-to-potassium ratio (Na/K) in a population sample to clarify the close relationship between Na/K and blood pressure level independently of potential confounding factors. [Methods]: Study participants consisted of 9144 apparently healthy citizens (aged 54 ± 13 years). All clinical parameters were obtained at baseline. [Results]: Na/K was significantly higher in hypertensive individuals irrespective of antihypertensive medication status (normotension, 3.12 ± 1.82; untreated hypertension 3.50 ± 1.96; treated hypertension, 3.72 ± 2.53). As urinary Na ([beta] = 0.092, P < 0.001) and K ([beta] = -0.050, P < 0.001) levels were inversely associated with BP, Na/K ([beta] = 0.118, P < 0.001) was more closely associated with BP than Na or K alone, as well as daily salt intake estimated from urinary Na ([beta] = 0.088, P < 0.001). Several factors were significantly associated with Na/K, namely age, sex, obesity, blood pressure, renal function, salt restriction status, serum phosphate and urinary creatinine level, and fasting period and season at urine sample collection. However, the association between Na/K and BP was independent of these factors (adjusted [beta] = 0.112, P < 0.001). No direct association was observed between Na/K and large arterial remodeling assessed by pulse wave analysis (P = 0.496) or retinal arteriolar morphological change (P = 0.431). Further, a genome-wide association study failed to identify any particular genotype influencing urinary Na and K levels. [Conclusions]: Although we clarified several factors that might affect spot urine Na/K, these relationships were not substantial enough to confound the association between urinary Na/K and BP. A simple measure of Na/K might be more representative of salt loading obtained from spot urine samples than Na excretion alone.

Purpose To correlate a genetic risk score based on age-related macular degeneration (AMD) susceptibility genes with the risk of AMD in the second eye. Methods This is a retrospective, open cohort study consisting of 891 unilateral AMD patients, who were followed for at least 12 months and recruited from three institutes. DNAs were genotyped using Illumina OmniExpress, HumanOmni2.5-8, and/or HumanExome. Survival analyses and Cox proportional hazard models were used to examine the association between 11 AMD susceptibility genes and the duration until second-eye involvement in 499 samples from Kyoto University, which were replicated in two other cohorts. Genetic risk score (GRS) was also evaluated. Results The ARMS2 rs10490924 recessive model (hazard ratio [HR]meta = 2.04; Pmeta = 3.4 × 10⁻³) and CFH rs800292 additive model (HRmeta = 1.77; Pmeta = 0.013) revealed significant associations with second-eye involvement. The dominant model of TNFRSF10A rs13278062, VEGFA rs943080, and CFI rs4698775 showed consistent effects across three datasets (I² = 0%; HRmeta = 1.46, 1.30, 1.51, respectively). The GRS using these five single nucleotide polymorphisms (SNPs) was also significantly associated (HRmeta [per score] = 2.42; P = 2.2 × 10⁻⁵; I² = 0%). After 10 years from the first visit, the patients within the top 10% by GRS showed a 51% hazard rate, in contrast to 2.3% among patients within the lowest 10% by GRS. Conclusions We demonstrated that the GRS using ARMS2, CFH, TNFRSF10A, VEGFA, and CFI was significantly associated with second-eye involvement. Genetic risk has high predictive ability for second-eye involvement of AMD.

Alpha-1 antitrypsin (AAT) encoded by SERPINA1 is an acute-phase inflammation marker, and AAT deficiency (AATD) is known as one of the common genetic disorders in European populations. However, no genetic determinants to AAT levels apart from the SERPINA gene clusters have been identified to date. Here we perform a genome-wide association study of serum AAT levels followed by a two-staged replication study recruiting a total of 9,359 Japanese community-dwelling population. Three missense variants of metabolic syndrome-related genes, namely, rs671 in ALDH2, rs1169288 in HNF1A and rs1260326 in GCKR, significantly associate with AAT levels (P≤1.5 × 10−12). Previous reports have shown the functional relevance of ALDH2 and HNF1A to AAT. We observe a significant interaction of rs671 and alcohol consumption on AAT levels. We confirm the association between AAT and rs2896268 in SERPINA1, which is independent of known causative variants of AATD. These findings would support various AAT functions including metabolic processes., Alpha-1 antitrypsin deficiency is a common genetic disorder in Europeans. Here Setoh et al. perform a genome-wide association study of AAT serum levels in a Japanese population and find three missense variants in the metabolism genes ALDH2, HNF1A and GCKR.

Age-related macular degeneration (ARMD) is the leading cause of blindness in the elderly population not only Western but also Asian industrial countries. In Caucasian, a polymorphism of the complement factor H gene (CFH), the C allele of rs1061170 (Y402H), was established as the first strong genetic factor for excursively exudative type of ARMD. In this study, we performed an extensive sequencing of the 22 exons in the CFH gene by recruiting 146 exudative ARMD patients and 105 normal controls of Japanese origin and identified 61 polymorphisms. We found that the frequency of the C allele of rs1061170 (Y402H) is much lower (0.04) in Japanese controls than in Caucasians (0.45). No case disease susceptibility to exudative ARMD was noted for rs1061170 (Y402H) (χ 2 = 3.19, P corr = 0.423), or other 12 single nucleotide polymorphisms (SNPs) whose frequency is greater than 0.05. When haplotypes were inferred for 13 SNPs (these 12 SNPs with a frequency greater than 0.05 and rs1061170), three haplotypes whose pattern was similar to those in Caucasians were identified but with substantial difference in frequency. Again we failed to identify genetic association between Japanese exudative ARMD and any of the haplotypes including the J1 haplotype which was shown to be susceptible to ARMD in Caucasians (χ 2 = 3.92, P corr = 0.157). CFH does not appear to be a primary hereditary contributor to ARMD in Japanese. The absence of CFH contribution to ARMD in Japanese may correlate with the findings in ethnic differences of ARMD phenotypes.

Antibodies against citrullinated proteins are highly specific for rheumatoid arthritis. We previously reported that functional variants of the gene encoding peptidylarginine deiminase type 4 were closely associated with RA. The purpose of this study was to investigate the citrullinated autoantigens recognized by serum samples from patients with RA. The human chondrocyte cDNA expression library was citrullinated by PADI4 and was immunoscreened with anti-modified citrulline antibodies and sera from patients with rheumatoid arthritis. One immunoreactive cDNA clone containing a 2480-base pair insert was isolated and sequence analysis revealed that the cDNA included a part of the eukaryotic translation initiation factor 4G1. Immunoreactivity against a recombinant citrullinated eIF4G1 fragment was observed with high specificity in 50.0% of RA patients. The levels of antibodies against citrullinated eIF4G1 were correlated with those of anti-CCP antibodies. Citrullinated eIF4G1 was identified as a candidate citrullinated autoantigen in RA patients. Citrullination of eIF4G1 may thus be involved in the pathogenesis of RA.

Rheumatoid arthritis (RA) is one of the most common autoimmune diseases, but its autoimmune mechanisms are not clearly understood. Recently, anti-citrullinated peptide antibodies have been specifically observed in sera of RA patients. Furthermore, we identified RA-susceptible variant in a gene encoding citrullinating enzyme, peptidylarginine deiminase type 4 (PADI4). Therefore, we hypothesized that proteins which are modified in RA synovium by PADI4 act as autoantigens. Subsequently, we obtained human collagen type I (huCI) as one of the autoantigens using a RA synoviocyte cDNA library by immunoscreening. We also investigated that the levels of anti-citrullinated huCI were significantly higher in RA patient sera than in normal control sera with high specificity (99%) and positively correlated with the levels of anti-cyclic citrullinated peptide (anti-CCP) antibodies. We concluded that huCI is a novel substrate protein of PADIs and that citrullinated huCI is a candidate autoantigen of RA.

Peptidylarginine deiminase (PADI) catalyses the post-translational modification of arginine to citrulline, which is specifically recognized by sera from rheumatoid arthritis (RA) patients. The PADI4 gene has recently been identified as a risk factor for RA. We aimed to determine whether PADI4 constitutes an autoantigen in RA.Serum samples were obtained from 42 patients with RA, 19 patients with systemic lupus erythematosus (SLE), 23 patients with other rheumatic diseases, and 40 normal individuals. The presence of antibodies against recombinant human PADI4 (anti-PADI4) was examined using enzyme-linked immunosorbent assay (ELISA) and Western blotting.For ELISA, the prevalence of anti-PADI4 among RA patients (50%) was significantly higher than that of normal individuals (2.5%), SLE (10.5%), and other rheumatic diseases (4.3%), while for Western blot analysis, PADI4 was recognized only by a portion of the ELISA-positive serum samples.PADI4 is an autoantigen in some RA patients, and its conformational epitope(s) may be important.

Immunoglobulin A (IgA) nephropathy is the most common form of primary glomerulonephritis worldwide. The pathogenesis of IgA nephropathy is unknown, but it is certain that some genetic factors are involved in susceptibility to the disease. Employing a large-scale, case-control association study using gene-based single-nucleotide polymorphism (SNP) markers, we previously reported four candidate genes. We report here an additional significant association between IgA nephropathy and an SNP located in the gene encoding immunoglobulin micro-binding protein 2 (IGHMBP2) at chromosome 11q13.2-q13.4. The association (chi2 =17.1, p = 0.00003; odds ratio of 1.85 with 95% confidence interval of 1.39-2.50 in a dominant association model) was found using DNA from 465 affected individuals and 634 controls. The SNP (G34448A) caused an amino acid substitution from glutamine to lysine (E928K). As the gene product is involved in immunoglobulin-class switching and patients with the A allele revealed higher serum levels of IgA (p = 0.048), the amino acid change might influence a class switch to increase serum IgA levels, resulting in a higher risk of IgA nephropathy.

Objective To examine the entire HLA region for loci (other than the DRB1 locus) associated with rheumatoid arthritis (RA) susceptibility, by typing HLA–DRB1 alleles and multiple single-nucleotide polymorphisms (SNPs) in the Japanese population. Methods The HLA–DRB1 alleles and 88 SNPs distributed over the HLA gene complex were genotyped, for 828 patients with RA and 1,032 control subjects. The data were evaluated for linkage disequilibrium, and case–control associations were analyzed in 2 ways, in the presence or absence of the disease-susceptibility DRB1 allele, to detect loci independent of the DRB1 allele. Results HLA–DRB1 alleles *0405, *0401, *0901, *0101, *1401, *1602, *0403, and *1405 were significantly associated with RA in the Japanese population. The smallest P value (P = 1.4 × 10−27) was observed in association with an intronic SNP of the NOTCH4 gene, which was due to strong linkage disequilibrium with the HLA–DRB1 allele. A strong association that was independent of HLA–DRB1 shared epitope alleles was observed in 2 SNPs: one in the intron of the MICA gene, the other in the intron of the HLA–DQB2 gene. Their association with RA, independent of HLA–DRB1 shared epitope alleles, was suggestive (P = 0.0024 [corrected P (Pcorr) = 0.068, and P = 0.00037 [Pcorr = 0.012], respectively). Conclusion These findings suggest that 1 or more other loci besides the HLA–DRB1 or other DRB1 (non–shared epitope, non-*0901) alleles are involved in RA susceptibility/protection.

Rheumatoid arthritis is a common inflammatory disease with complex genetic components. We investigated the genetic contribution of the cytokine gene cluster in chromosome 5q31 to susceptibility to rheumatoid arthritis in the Japanese population by case-control linkage disequilibrium (LD) mapping using single nucleotide polymorphisms (SNPs). Here we report that there is significant association between rheumatoid arthritis and the organic cation transporter gene SLC22A4 (P = 0.000034). We show that expression of SLC22A4 is specific to hematological and immunological tissues and that SLC22A4 is also highly expressed in the inflammatory joints of mice with collagen-induced arthritis. A SNP affects the transcriptional efficiency of SLC22A4 in vitro, owing to an allelic difference in affinity to Runt-related transcription factor 1 (RUNX1), a transcriptional regulator in the hematopoietic system. A SNP in RUNX1 is also strongly associated with rheumatoid arthritis (P = 0.00035). Our data indicate that the regulation of SLC22A4 expression by RUNX1 is associated with susceptibility to rheumatoid arthritis, which may represent an example of an epistatic effect of two genes on this disorder.

Individuals with rheumatoid arthritis frequently have autoantibodies to citrullinated peptides, suggesting the involvement of the peptidylarginine deiminases citrullinating enzymes (encoded by PADI genes) in rheumatoid arthritis. Previous linkage studies have shown that a susceptibility locus for rheumatoid arthritis includes four PADI genes but did not establish which PADI gene confers susceptibility to rheumatoid arthritis. We used a case-control linkage disequilibrium study to show that PADI type 4 is a susceptibility locus for rheumatoid arthritis (P = 0.000008). PADI4 was expressed in hematological and rheumatoid arthritis synovial tissues. We also identified a haplotype of PADI4 associated with susceptibility to rheumatoid arthritis that affected stability of transcripts and was associated with levels of antibody to citrullinated peptide in sera from individuals with rheumatoid arthritis. Our results imply that the PADI4 haplotype associated with susceptibility to rheumatoid arthritis increases production of citrullinated peptides acting as autoantigens, resulting in heightened risk of developing the disease.

Immunoglobulin A nephropathy (IgAN) is a primary glomerulonephritis of common incidence world-wide whose etiology and pathogenesis remain unresolved, although genetic factors are assumed to be involved in the development and progression of this disease. To identify genetic variations that might confer susceptibility to IgAN, we performed a case-control association study involving 389 Japanese IgAN patients and 465 controls. Genome-wide analysis of approximately 80,000 single-nucleotide polymorphisms (SNPs) identified a significant association between IgAN and six SNPs located in the PIGR (polymeric immuoglobulin receptor) gene at chromosome 1q31-q41. One of them, PIGR-17, caused an amino-acid substitution from alanine to valine at codon 580 (chi(2)=13.05, P=0.0003, odds ratio [OR] =1.59, 95% confidence interval [95% CI] =1.24-2.05); the OR of minor homozygotes to others was 2.71 (95% CI=1.31-5.61). Another SNP, PIGR-2, could affect promoter activity (chi(2)=11.95, P=0.00055, OR=1.60, 95% CI=1.22-2.08); the OR of minor homozygotes to others was 2.08 (95% CI=0.94-4.60). Pairwise analyses demonstrated that all six SNPs were in almost complete linkage disequilibrium. Biopsy specimens from IgAN patients were positively stained by antibody against the secretory component of PIGR, but corresponding tissues from non-IgAN patients were not. Our results suggest that a gene associated with susceptibility to IgAN lies within or close to the PIGR gene locus on chromosome 1q in the Japanese population.

Osteoarthritis (OA) is one of the most common diseases in the elderly. Although its pathophysiology is complex and its molecular basis remains to be determined, much evidence suggests that OA has strong genetic determinants. To search for susceptibility loci of OA, we selected seven candidate genes encoding cartilage-specific collagens (type II, IX, X, and XI collagens) and performed association analysis for OA using single nucleotide polymorphisms (SNPs) in the coding region of these genes. Four hundred seventeen OA samples and 280 control samples were collected from the Japanese population, and 12 SNPs were genotyped. Our studies have identified two susceptibility loci of OA: COL2A1 and COL9A3. An SNP in COL9A3 showed significant association with knee OA (p = 0.002, odds ratio [OR] = 1.48). Haplotype analysis showed significant association between a specific haplotype of COL2A1 and hip OA (p = 0.024; OR = 1.30). Further analysis of these two genes will shed light on the molecular mechanisms of OA.

Although various risk factors have been identified for the development of age-related macular degeneration (AMD), risk factors of early AMD have been relatively under studied. We aimed to investigate AMD risk factors by evaluating multiple factors in association with large drusen, an important component of AMD, simultaneously. In a community-based cross-sectional survey in Japan, 971 large drusen cases and 3,209 controls were compared for 65 variables, including systemic, environmental and genetic factors. The association and the effect size of each factor were evaluated with logistic regression analysis using a backward-elimination approach. Multivariate analyses identified a significant association in serum calcium level (odds ratio [OR] = 0.932, P = 1.05 × 10−3), ARMS2 A69S (rs10490924) genotype (OR = 1.046, P < 0.001), Chlamydia pneumoniae IgG (OR = 1.020, P = 0.0440) and age (OR = 1.013, P < 0.001) for large drusen. Hypocalcemia was observed in 7.2% of large drusen cases and in 5.5% of controls (P = 0.0490). C. pneumoniae infections was more frequent in large drusen cases (56.4%) than in conrols (51.7%, P = 0.00956). These results suggest that calcium, ARMS2 genotype, C. pneumonia infection and age are significant factors in the development of the early stages of AMD.

Central blood pressure (BP) has been suggested to be a better predictor of cardiovascular disease risk than brachial BP. Given that central BP and arterial waveform are both influenced by insulin resistance, major initiators of insulin resistance, such as serum–free fatty acid (FFA), are suspected of potentially being involved in central hemodynamics. To confirm that insulin signaling is an important modulator of central hemodynamics, we investigated this hypothesis in a large-scale general population. Brachial BP and radial arterial waveform were measured simultaneously in 9393 middle-aged to elderly individuals. The augmentation index was calculated from the radial waveform as the ratio of the height of the late systolic peak to that of the first peak. Central systolic BP was defined as the absolute pressure of the late systolic peak of the waveform. Differences in central and brachial pulse pressure (PP) were considered to represent PP amplification. PP amplification differed significantly among serum FFA level quartiles (Q1, 7.8±5.3; Q2, 8.6±5.0; Q3, 9.3±5.7; Q4, 10.3±6.1 mm Hg; P β =0.145, P β =−0.122, P β =−0.044, P β =0.022, P