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Background: Long-term exposure to air pollution has been found to contribute to the development of cognitive decline. Our study aimed to assess the association between various air pollutants and cognitive impairment and dementia. Additionally, explore the modification effects of lifestyle and genetic predisposition. Methods: The exposure levels to various air pollutants, including particulate matter (PM) with diameters ≤ 2.5 (PM2.5), ≤ 10 (PM10), and between 2.5 and 10 μm (PM2.5−10) and nitrogen oxides (NO and NO2) were identified. An air pollution score (APS) was calculated to evaluate the combined exposure to these five air pollutants. A genetic risk estimate and healthy lifestyle score (HLS) were also generated. The Cox regression model adjusted by potential confounders was adopted to access the association between pollution exposure and cognitive decline, and several sensitivity analyses were additionally conducted to test the robustness. Results: The combined exposure to air pollutants was associated with an increased risk of incident cognitive decline. Compared with the low exposure group, the hazard ratio (HR) and 95% confidence interval (CI) for all-cause dementia, Alzheimer's dementia, vascular dementia, and mild cognitive impairment (MCI) in those exposed to the highest levels of air pollutants were respectively 1.07 (95% CI: 1.04 to 1.09), 1.08 (95% CI: 1.04 to 1.12), 1.07 (95% CI: 1.02 to 1.13), and 1.19 (95% CI: 1.12 to 1.27). However, the modification effects from genetic predisposition were not widely observed, while on the contrary for the healthy lifestyle. Our findings were proven to be reliable and robust based on the results of sensitivity analyses. Conclusions: Exposure to air pollution was found to be a significant contributing factor to cognitive impairment and dementia, and this association was not easily modified by an individual's genetic predisposition. However, adopting a healthy lifestyle may help to manage the risk of cognitive decline related to air pollution. [ABSTRACT FROM AUTHOR]

Objectives: Unhealthy sleep behaviors may be potential risk factors for chronic kidney disease (CKD). We aimed to examine the associations of combined sleep patterns and genetic susceptibility with incident CKD. Methods: This large-scale prospective cohort study included 370,671 participants without CKD at baseline (2006–2010) in UK Biobank data. Five sleep behaviors were made up of sleep duration, insomnia, snoring, chronotype, and daytime sleepiness according to questionnaire. Overall sleep patterns by summing the five scores were created. Weighted genetic risk score of kidney function was calculated. Incident CKD was recorded from death register, primary care, and hospital inpatient records. A subset of 41,130 individuals who participated both the initial assessment visit and follow-up visit (2012+) was also used. Results: During a median follow-up of 10.6 years (about 3.9 million person-years), we documented 6,365 patients with incident CKD. In five sleep behaviors, sleep 7–8 h/day, free of insomnia and no frequent daytime sleepiness were independently associated with incident CKD, with a 12% (95%CI 7–16), 9% (3–14), 13% (9–18) lower risk, respectively. Compared to those with a sleep score of 0–1, participants with a score of 5 had a 21% (10–31%) lower risk of CKD. 17.1% of CKD in this cohort could be attributed to total poor sleep pattern. Participants with high genetic risk and intermediate or poor sleep pattern showed the highest risk of CKD (OR = 2.58, 95%CI 2.24–2.96; OR = 2.59, 95%CI 2.02–3.32, respectively), although there was no significant interaction between sleep patterns and genetic risk categories. Among individuals who participated both the initial assessment visit and follow-up visit, we found that the association between amelioration of sleep pattern and risk of CKD was significant after fully adjustment (OR = 0.60, 95%CI 0.36–0.99), compared with group of stable sleep pattern. Conclusion: In this large prospective study, participants with a healthy sleep pattern was associated with a significant reduction of incident CKD risk no matter they had a high, intermediate, or low genetic risk. [ABSTRACT FROM AUTHOR]

In observational studies of children and adolescents, higher body weight has been associated with distinct disease outcomes, including cancer, in adulthood. Therefore, we performed a two‐sample Mendelian randomization (MR) study to evaluate the causal effect of childhood obesity on long‐term cancer risk. Single‐nucleotide polymorphisms associated with higher childhood body mass index (BMI) from large‐scale genome‐wide association studies were used as genetic instruments. Summary‐level data for 24 site‐specific cancers were obtained from UK Biobank. We found that a 1‐SD increase in childhood BMI (kg/m2) was significantly associated with a 60% increase in risk of pancreatic cancer (odds ratio [OR]: 1.60; 95% confidence interval [CI]: 1.12‐2.28; P < 0.01) and a 47% increase in risk of esophageal cancer (OR: 1.47; 95% CI: 1.09‐1.97; P < 0.01) in adults. In contrast, there was an inverse association of genetic predisposition to childhood obesity with throat (OR: 0.46; 95% CI: 0.27‐0.79; P < 0.01) and breast cancer (OR: 0.77; 95% CI: 0.64‐0.94; P < 0.01) in adult life. For the other 20 cancers studied, no statistically significant association was observed. Our MR analyses found causal effects of childhood obesity on several cancers. Maintaining a healthy weight should be emphasized during childhood and adolescence to prevent cancer risk later in life. [ABSTRACT FROM AUTHOR]

Background: Depression is moderately heritable but there is no common genetic variant which has a major effect on susceptibility. It is possible that some very rare variants could have substantial effect sizes and these could be identified from exome sequence data.Methods: Data from 50,000 exome-sequenced UK Biobank participants was analysed. Subjects were treated as cases if they had reported having seen a psychiatrist for "nerves, anxiety, tension or depression". Gene-wise weighted burden analysis was performed to see if there were any genes or sets of genes for which there was an excess of rare, functional variants in cases.Results: There were 5,872 cases and 43,862 controls. There were 22,028 informative genes but no gene or gene set produced a statistically significant result after correction for multiple testing. None of the genes or gene sets with the lowest p values appeared to be a biologically plausible candidate.Limitations: The phenotype is based on self-report and the cases are likely to be somewhat heterogeneous. Likewise, it is expected that some of the subjects classed as controls will in fact have suffered from depression or some other psychiatric diagnosis. The number of cases is on the low side for a study of exome sequence data.Conclusions: The results conform exactly with the expectation under the null hypothesis. It seems unlikely that depression genetics research will implicate specific genes having a substantial impact on the risk of developing psychiatric illness severe enough to merit referral to a specialist until far larger samples become available. [ABSTRACT FROM AUTHOR]

Background: Primary hyperparathyroidism (PHPTH) is a common endocrine disorder and an estimated 10% of cases are hereditary, related to syndromes including; multiple endocrine neoplasia (MEN) type 1, MEN type 4, MEN2A and hereditary hyperparathyroidism‐jaw tumour syndrome. Establishing the underlying genetic cause for PHPTH allows for personalized and cost‐effective management. Familial hypocalicuric hypercalcaemia (FHH) is a benign disorder of hypercalcaemia associated with an inappropriately low urinary calcium excretion, which is quantified by the calcium creatinine clearance ratio (CCCR). Recent NHS England National Genomic Test Directory testing criteria for familial hyperparathyroidism state testing patients presenting with PHPTH and CCCR > 0.02 presenting (i) <35 years of age, or (ii) <45y with one of (a) multiglandular disease, or (b) hyperplasia on histology, or (c) ossifying fibroma(s) of the maxilla and/ or mandible, or (d) a family history of unexplained PHPTH. The testing criterion for FHH is a CCCR < 0.02. Aims and Methods: A retrospective review of patients referred for genetic testing over a 4 year period for suspected hereditary HPTH was performed. Genetic analysis was performed by next‐generation sequencing of the following genes; MEN1, CDC73, CASR, CDKN1A, CDKN1B, CDKN2B, CDKN2C, RET, GCM2, GNA11, and AP2S1 in NHS‐accredited Regional Genetic laboratories. Aims of this study were to better define testing criteria for suspected hereditary PHPTH in a UK cohort. Results: A total of 121 patients were included in this study (92 female) with a mean age of 41 years (SD 17). A pathogenic germline variant was identified in 16% (n = 19). A pathogenic variant was identified in the PHPTH genes CDC73 in a single patient and MEN1 in six patients (6% of total), in the FHH genes, CASR in 11 patients and AP2S1 in a single paediatric case (10% of total). A variant of uncertain significance (VUS) was identified in eight patients (6%) but over the course of this study familial segregation studies and computational analysis enabled re‐classification of four of the variants, with two VUS's in the CASR gene being upgraded to likely pathogenic variants. Age at diagnosis and multiglandular disease as sole risk factors were not predictive of a pathogenic germline variant in this cohort but a positive family history was strongly predictive (P =.0002). A significant difference in the mean calcium creatinine clearance ratio (CCCR) in those patients with an identified CASR pathogenic variant versus those without (P =.0001) was demonstrated in this study. Thirty‐three patients were aged over 50 years and the diagnostic rate of a pathogenic variant was 15.1% in those patients >50 years of age compared to 15.9% in those <50 years. Five patients >50 years and with a CCCR of <0.01, were diagnosed with a pathogenic variant in CASR. Conclusion: Family history was the strongest predictor of hereditary PHPTH in this cohort. This study has highlighted the importance of re‐evaluating VUS's in order to inform patient management and enable appropriate genetic counselling. Finally, this study has demonstrated the need to consider genetic testing for PHPTH in patients of any age, particularly those with additional risk factors. [ABSTRACT FROM AUTHOR]

The pathological mechanisms associated with the occurrence and development of Behcet's disease (BD) are not yet known. Two large genome-wide association surveys revealed an association between interleukin (IL)-23R single nucleotide polymorphism and BD. This study aimed to investigate the association between IL-23R gene polymorphisms and BD susceptibility. Comprehensive literature search was performed across four online databases – PubMed, Embase, Cochrane Library, and Web of science. The included studies had to be published before May 15, 2019. The Newcastle–Ottawa scale was used to assess the quality of every included study, and pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using the allele model of inheritance to evaluate the potential associations between IL-23R gene polymorphisms and BD risk. In all, 12 case-control studies comprising 6,926 BD patients and 10,211 controls were identified and included in this meta-analysis, in which 5 loci of IL-23R gene polymorphisms were investigated. Of these 5 loci, 2 were found to be significantly associated with BD susceptibility: rs17375018 (G vs. A, OR = 1.50, 95% CI: 1.34–1.68, P <.00001) and rs924080 (T vs. C, OR = 1.36, 95% CI: 1.29–1.43, P <.00001). Only a systematic review was conducted for rs12119179, rs11209032, and rs12141431, owing to the lack of sufficient data. This meta-analysis indicated that rs17375018 (G/A) and rs924080 (T/C) were associated with BD susceptibility. However, association of the other IL-23R polymorphisms could not be estimated owing to the lack of studies. BD: Behcet's disease; SNP: single nucleotide polymorphism; HLA: human leukocyte antigen; IL: interleukin; OR: odds ratio; CI: confidence interval; HWE: Hardy–Weinberg equilibrium; UK: United Kingdom; NOS: Newcastle–Ottawa scale; GWAS: genome-wide association study; TNF-α: tumor necrosis factor-α [ABSTRACT FROM AUTHOR]

Supplemental digital content is available in the text. Purpose: Polygenic risk scores (PRS) summarize genome-wide genotype data into a single variable that produces an individual-level risk score for genetic liability. PRS has been used for prediction of chronic diseases and some risk factors. As PRS has been studied less for physical activity (PA), we constructed PRS for PA and studied how much variation in PA can be explained by this PRS in independent population samples. Methods: We calculated PRS for self-reported and objectively measured PA using UK Biobank genome-wide association study summary statistics, and analyzed how much of the variation in self-reported (MET-hours per day) and measured (steps and moderate-to-vigorous PA minutes per day) PA could be accounted for by the PRS in the Finnish Twin Cohorts (FTC; N = 759–11,528) and the Northern Finland Birth Cohort 1966 (NFBC1966; N = 3263–4061). Objective measurement of PA was done with wrist-worn accelerometer in UK Biobank and NFBC1966 studies, and with hip-worn accelerometer in the FTC. Results: The PRS accounted from 0.07% to 1.44% of the variation (R 2) in the self-reported and objectively measured PA volumes (P value range = 0.023 to <0.0001) in the FTC and NFBC1966. For both self-reported and objectively measured PA, individuals in the highest PRS deciles had significantly (11%–28%) higher PA volumes compared with the lowest PRS deciles (P value range = 0.017 to <0.0001). Conclusions: PA is a multifactorial phenotype, and the PRS constructed based on UK Biobank results accounted for statistically significant but overall small proportion of the variation in PA in the Finnish cohorts. Using identical methods to assess PA and including less common and rare variants in the construction of PRS may increase the proportion of PA explained by the PRS. [ABSTRACT FROM AUTHOR]

Currently in the United Kingdom, anyone donating gametes has the status of an open-identity donor. This means that, at the age of 18, persons conceived with gametes donated since April 1, 2005 have a right to access certain pieces of identifying information about their donor. However, in early 2015, the UK Parliament approved new regulations that make mitochondrial donors anonymous. Both mitochondrial donation and gamete donation are similar in the basic sense that they involve the contribution of gamete materials to create future persons. Given this similarity, this paper presumes that both types of donor should be treated the same and made open-identity under the law, unless there is a convincing argument for treating them differently. I argue that none of the existing arguments that have been made so far in favor of mitochondrial donor anonymity are convincing and mitochondrial donors should therefore be treated as open-identity donors under UK law. [ABSTRACT FROM AUTHOR]

Background: Cleft lip and/or palate (CL/P) is one of the most common birth conditions in the world, but little is known about its causes. Professional opinion remains divided as to which treatments may be the most beneficial for patients with CL/P, and the factors that contribute to psychological adjustment are poorly understood. The use of different methodological approaches and tools plays a key role in hampering efforts to address discrepancies within the evidence base. A new UK-wide program of research, The Cleft Collective, was established to combat many of these methodological challenges and to address some of the key research questions important to all CL/P stakeholders. Objective: To describe the establishment of CL/P cohort studies in the United Kingdom and to consider the many opportunities this resource will generate. Results: To date, protocols have been developed and implemented within most UK cleft teams. Biological samples, environmental information, and data pertaining to parental psychological well-being and child development are being collected successfully. Recruitment is currently on track to meet the ambitious target of approximately 9800 individuals from just more than 3000 families. Conclusions: The Cleft Collective cohort studies represent a significant step forward for research in the field of CL/P. The data collected will form a comprehensive resource of information about individuals with CL/P and their families. This resource will provide the basis for many future projects and collaborations, both in the United Kingdom and around the world. [ABSTRACT FROM AUTHOR]

Alcoholic liver disease (ALD) and, increasingly, non-alcoholic fatty liver disease (NAFLD) are common causes of advanced liver disease in many developed countries including the UK. Both diseases share parallel natural histories, progressing from steatosis, to steatohepatitis and fibrosis/cirrhosis; and are characterised by substantial interindividual variation in disease outcome. This article will provide an overview of disease mechanisms, genetic modifiers and management, focusing principally on NAFLD, while drawing parallels between the two conditions where appropriate. [ABSTRACT FROM AUTHOR]

Chronic widespread musculoskeletal pain (CWP) is common, having a population prevalence of 10%. This study aimed to define the biological basis of the CWP/body mass association by using a systems biology approach. Adult female twins (n = 2444) from the TwinsUK registry who had extensive clinical, anthropometric, and "omic" data were included. Nontargeted metabolomics screening including 324 metabolites was carried out for CWP and body composition using dual-energy X-ray absorptiometry. The biological basis of these associations was explored through a genome-wide association study and replicated in an independent population sample (Cooperative Health Research in the Region of Augsburg [KORA] study, n = 2483). A causal role for the genetic variants identified was sought in CWP using a Mendelian randomisation study design. Fat mass/height2 was the body composition variable most strongly associated with CWP (TwinsUK: P = 2.4 × 10(-15) and KORA: P = 1.59 × 10(-10)). Of 324 metabolites examined, epiandrosterone sulfate (EAS) was highly associated with both CWP (P = 1.05 × 10(-09) in TwinsUK and P = 3.70 × 10(-06) in KORA) and fat mass/height2. Genome-wide association study of EAS identified imputed single nucleotide polymorphism rs1581492 at 7q22.1 to be strikingly associated with EAS levels (P ≤ 2.49 × 10(-78)), and this result was replicated in KORA (P = 2.12 × 10(-9)). Mendelian randomization by rs1581492 genotype showed that EAS is unlikely to be causally related to CWP. Using an agnostic omics approach to focus on the association of CWP with body mass index, we have confirmed a steroid hormone association and identified a genetic variant upstream of the CYP genes, which likely controls this response. This study suggests that steroid hormone abnormalities result from pain rather than causing it, and EAS may provide a biomarker that identifies subgroups at risk of CWP. [ABSTRACT FROM AUTHOR]

BACKGROUND: Sleep duration is attracting increasing attention in relation to chronic disease risk, but few large-scale studies have investigated the determinants of sleep characteristics in early life. In this study we used data from a large, population-based twin study to examine genetic and environmental influences on sleep duration and sleep difficulties in infancy. METHODS: Participants were 1931 pairs of young twins (3862 children) from the Gemini twin birth cohort. Sleep patterns were assessed at 15 months by using a modification of the Brief Infant Sleep Questionnaire completed by parents. Outcomes included nighttime and daytime sleep duration and frequency of night waking. RESULTS: Twin analyses showed that nighttime sleep duration was predominantly influenced by the shared environment (66%, confidence interval [CI] 63%-70%) with a modest genetic effect (26%, CI 22%-30%). A similar pattern was observed for daytime nap duration (shared environment: 57%, CI 53%-62%; genetic effect: 37%, CI 33%-41%) and sleep disturbance (shared environment: 55%, 44%-64%) with a genetic effect of 40% (30%-51%). These estimates were similar for boys and girls. CONCLUSIONS: These results indicate an important contribution of the shared family environment as well as genes to children's sleep behavior. There is a need for research to identify specific environmental determinants that could provide targets for interventions to improve sleep quality. [ABSTRACT FROM AUTHOR]

Background: Brain iron deposition occurs in dementia. In European ancestry populations, the HFE p.C282Y variant can cause iron overload and hemochromatosis, mostly in homozygous males., Objective: To estimate p.C282Y associations with brain MRI features plus incident dementia diagnoses during follow-up in a large community cohort., Methods: UK Biobank participants with follow-up hospitalization records (mean 10.5 years). MRI in 206 p.C282Y homozygotes versus 23,349 without variants, including T2* measures (lower values indicating more iron)., Results: European ancestry participants included 2,890 p.C282Y homozygotes. Male p.C282Y homozygotes had lower T2* measures in areas including the putamen, thalamus, and hippocampus, compared to no HFE mutations. Incident dementia was more common in p.C282Y homozygous men (Hazard Ratio HR = 1.83; 95% CI 1.23 to 2.72, p = 0.003), as was delirium. There were no associations in homozygote women or in heterozygotes., Conclusion: Studies are needed of whether early iron reduction prevents or slows related brain pathologies in male HFE p.C282Y homozygotes.

Background: The metabolic syndrome (MetS) is a description of a clustering of cardiometabolic risk factors in the same individual. Previous genome-wide association studies (GWASs) have identified 29 independent genetic loci linked to MetS as a binary trait. This study used data from UK biobank to search for additional loci. Methods: Using data from 291,107 individuals in the UK biobank, a GWAS was performed versus the binary trait MetS (harmonized NCEP criteria). Results: In a GWAS of MetS (binary) we found 93 independent loci with P  < 5 × 10 -8 , of which 80 were not identified in previous GWASs of MetS. However, the majority of those loci have previously been associated with one or more of the five MetS components. Of particular interest are the genes being related to MetS (binary) in this study, but not to any of the MetS components in past studies, such as WDR48, KLF14, NAADL1, GADD45G, and OR5R1, as well as the two loci that have been associated with all five MetS components in past studies, SNX10 and C5orf67. A pathway analysis of the 93 independent loci showed the immune system, transportation of small molecules, and metabolism to be enriched. Conclusion: This GWAS of the MetS in UK biobank identified several new loci being associated with MetS. Most of those have previously been found to be associated with different components of MetS, but several loci were found not previously linked to cardiometabolic disease.

The autosomal recessive spinocerebellar ataxias are an exciting field of study, with a growing number of causal genes and an expanding phenotypic spectrum. SYNE1 was originally discovered in 2007 as the causal gene underlying autosomal recessive spinocerebellar ataxia 1, a disease clinically thought to manifest with mainly pure cerebellar ataxia. Since the original report SYNE1 mutations have also been identified in families with motor neuronopathy and arthrogryposis but few families have been screened as the gene is very large at 146 exons in length. We screened 196 recessive and sporadic ataxia patients for mutations in SYNE1 using next generation sequencing in order to assess its frequency and extend the clinicogenetic spectrum. We identified four novel truncating mutations spread throughout the SYNE1 gene from three families living in London that originated from England, Turkey and Sri Lanka. The phenotype was mainly pure cerebellar ataxia in two families, cognitive decline was present in all three families, axonal neuropathy in one family and marked spasticity in the Turkish family, with a range of disease severities. Searching for genotype-phenotype correlations in the SYNE1 gene, defects located near the 3' prime end of the gene are more frequently associated with motor neuron or neuromuscular involvement so far. Our data indicate SYNE1 mutations are not an uncommon cause of recessive ataxia with or without additional clinical features in patients from various ethnicities. The use of next generation sequencing allows the rapid analysis of large genes and will likely reveal more SYNE1 associated cases and further expand genotype-phenotype correlations.

The hereditary spastic paraplegias are a heterogeneous group of degenerative disorders that are clinically classified as either pure with predominant lower limb spasticity, or complex where spastic paraplegia is complicated with additional neurological features, and are inherited in autosomal dominant, autosomal recessive or X-linked patterns. Genetic defects have been identified in over 40 different genes, with more than 70 loci in total. Complex recessive spastic paraplegias have in the past been frequently associated with mutations in SPG11 (spatacsin), ZFYVE26/SPG15, SPG7 (paraplegin) and a handful of other rare genes, but many cases remain genetically undefined. The overlap with other neurodegenerative disorders has been implied in a small number of reports, but not in larger disease series. This deficiency has been largely due to the lack of suitable high throughput techniques to investigate the genetic basis of disease, but the recent availability of next generation sequencing can facilitate the identification of disease-causing mutations even in extremely heterogeneous disorders. We investigated a series of 97 index cases with complex spastic paraplegia referred to a tertiary referral neurology centre in London for diagnosis or management. The mean age of onset was 16 years (range 3 to 39). The SPG11 gene was first analysed, revealing homozygous or compound heterozygous mutations in 30/97 (30.9%) of probands, the largest SPG11 series reported to date, and by far the most common cause of complex spastic paraplegia in the UK, with severe and progressive clinical features and other neurological manifestations, linked with magnetic resonance imaging defects. Given the high frequency of SPG11 mutations, we studied the autophagic response to starvation in eight affected SPG11 cases and control fibroblast cell lines, but in our restricted study we did not observe correlations between disease status and autophagic or lysosomal markers. In the remaining cases, next generation sequencing was carried out revealing variants in a number of other known complex spastic paraplegia genes, including five in SPG7 (5/97), four in FA2H (also known as SPG35) (4/97) and two in ZFYVE26/SPG15 Variants were identified in genes usually associated with pure spastic paraplegia and also in the Parkinson's disease-associated gene ATP13A2, neuronal ceroid lipofuscinosis gene TPP1 and the hereditary motor and sensory neuropathy DNMT1 gene, highlighting the genetic heterogeneity of spastic paraplegia. No plausible genetic cause was identified in 51% of probands, likely indicating the existence of as yet unidentified genes., (© The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain.)