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Background: Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder of complex genetic architecture and is characterized by multiple motor tics and at least one vocal tic persisting for more than 1 year. Methods: We performed a genome-wide meta-analysis integrating a novel TS cohort with previously published data, resulting in a sample size of 6133 individuals with TS and 13,565 ancestry-matched control participants. Results: We identified a genome-wide significant locus on chromosome 5q15. Integration of expression quantitative trait locus, Hi-C (high-throughput chromosome conformation capture), and genome-wide association study data implicated the NR2F1 gene and associated long noncoding RNAs within the 5q15 locus. Heritability partitioning identified statistically significant enrichment in brain tissue histone marks, while polygenic risk scoring of brain volume data identified statistically significant associations with right and left thalamus volumes and right putamen volume. Conclusions: Our work presents novel insights into the neurobiology of TS, thereby opening up new directions for future studies.

Recent evidence has linked circadian rhythm dysregulation to an increased risk of metabolic disorders. This study explores a potential association between variation in genes regulating the endogenous circadian timing system (clock genes) and the risk of type 2 diabetes (T2D) in a sample of Greek elderly people.Variants within and upstream or downstream of PPARA, PPARD, CLOCK/TMEM165, PER1, PER2 and PER3 genes were genotyped in 716 individuals with T2D (A) and 569 normoglycemic controls (B), and allele frequencies were compared between the groups in a case control study design.Samples were genotyped on Illumina Human PsychArray. Permutation test analysis was implemented to determine statistical significance. To avoid the possibility of subjects with prediabetes being included in the control group, people with HbA1c5.7% and fasting glucose100 mg/dl comprised group C (n = 393), for whom a separate analysis was performed (secondary analysis).A protective role against T2D was identified for 14 variants in the PPARA gene. The rs7291444, rs36125344, rs6008384 in PKDREJ, located upstream of PPARA, and rs2859389 in UTS2, located upstream of PER3, demonstrated a protective role against T2D in both analyses. In contrast, rs6744132, located between HES6 and PER2, was positively correlated with T2D risk. Only in the secondary analysis, rs2278637 in VAMP2, located downstream of PER1, and rs11943456 in CLOCK/TMEM165 were found to confer protection against T2D. In a recessive model analysis of all groups, PPARD variants exhibited a protective role against disease.Our findings suggest a possible implication of clock genes in T2D susceptibility. Further studies are needed to clarify the mechanisms that connect circadian rhythm dysfunction and T2D pathogenesis.

BackgroundMyasthenia gravis (MG) is a rare autoimmune disorder affecting the neuromuscular junction (NMJ). Here, we investigate the genetic architecture of MG via a genome-wide association study (GWAS) of the largest MG data set analysed to date.MethodsWe performed GWAS meta-analysis integrating three different data sets (total of 1401 cases and 3508 controls). We carried out human leucocyte antigen (HLA) fine-mapping, gene-based and tissue enrichment analyses and investigated genetic correlation with 13 other autoimmune disorders as well as pleiotropy across MG and correlated disorders.ResultsWe confirmed the previously reported MG association with TNFRSF11A (rs4369774; p=1.09×10−13, OR=1.4). Furthermore, gene-based analysis revealed AGRN as a novel MG susceptibility gene. HLA fine-mapping pointed to two independent MG loci: HLA-DRB1 and HLA-B. MG onset-specific analysis reveals differences in the genetic architecture of early-onset MG (EOMG) versus late-onset MG (LOMG). Furthermore, we find MG to be genetically correlated with type 1 diabetes (T1D), rheumatoid arthritis (RA), late-onset vitiligo and autoimmune thyroid disease (ATD). Cross-disorder meta-analysis reveals multiple risk loci that appear pleiotropic across MG and correlated disorders.DiscussionOur gene-based analysis identifies AGRN as a novel MG susceptibility gene, implicating for the first time a locus encoding a protein (agrin) that is directly relevant to NMJ activation. Mutations in AGRN have been found to underlie congenital myasthenic syndrome. Our results are also consistent with previous studies highlighting the role of HLA and TNFRSF11A in MG aetiology and the different risk genes in EOMG versus LOMG. Finally, we uncover the genetic correlation of MG with T1D, RA, ATD and late-onset vitiligo, pointing to shared underlying genetic mechanisms.

AIM To investigate the association between circulating anti-dopamine D2 receptor (D2R) autoantibodies and the exacerbation of tics in children with chronic tic disorders (CTDs). METHOD One hundred and thirty-seven children with CTDs (108 males, 29 females; mean age [SD] 10y 0mo [2y 7mo], range 4-16y) were recruited over 18 months. Patients were assessed at baseline, at tic exacerbation, and at 2 months after exacerbation. Serum anti-D2R antibodies were evaluated using a cell-based assay and blinded immunofluorescence microscopy scoring was performed by two raters. The association between visit type and presence of anti-D2R antibodies was measured with McNemar's test and repeated-measure logistic regression models, adjusting for potential demographic and clinical confounders. RESULTS At exacerbation, 11 (8%) participants became anti-D2R-positive ('early peri-exacerbation seroconverters'), and nine (6.6%) became anti-D2R-positive at post-exacerbation ('late peri-exacerbation seroconverters'). The anti-D2R antibodies were significantly associated with exacerbations when compared to baseline (McNemar's odds ratio=11, p=0.003) and conditional logistic regression confirmed this association (Z=3.49, p

Diabetic type 2 patients compared to nondiabetic patients exhibit an increased risk of developing diabetic kidney disease (DKD), the leading cause of end-stage renal disease. Hyperglycemia, hypertension, oxidative stress (OS), and genetic background are some of the mechanisms and pathways implicated in DKD pathogenesis. However, data on OS pathway susceptibility genes show limited success and conflicting or inconclusive results. Our study is aimed at exploring OS pathway genes and variants which could be associated with DKD. We recruited 121 diabetes mellitus type 2 (DM2) patients with DKD (cases) and 220 DM2, non-DKD patients (control) of Greek origin and performed a case-control association study using genome-wide association data. PLINK and EIGENSOFT were used to analyze the data. Our results indicate 43 single nucleotide polymorphisms with their 21 corresponding genes on the OS pathway possibly contributing or protecting from DKD: SPP1, TPO, TTN, SGO2, NOS3, PDLIM1, CLU, CCS, GPX4, TXNRD2, EPHX2, MTL5, EPX, GPX3, ALOX12, IPCEF1, GSTA, OXR1, GPX6, AOX1, and PRNP. Therefore, a genetic OS background might underlie the complex pathogenesis of DKD in DM2 patients.

Background: Approximately one third of type 2 diabetes mellitus (T2DM) cases present with diabetic nephropathy (DN), the leading cause of end-stage renal disease. Inflammation plays an important role in T2DM disease and DN pathogenesis. NLRP3 inflammasomes are complexes that regulate interleukin-1B (IL-1B) and IL-18 secretion, both involved in inflammatory responses. Activation of NLRP3 is associated with DN onset and progression. Here, we explore whether DN is associated with variants in genes encoding key members of the NLRP3 inflammasome pathway. Methods: Using genome-wide association data, we performed a pilot case-control association study, between 101 DN-T2DM and 185 non-DN-T2DM cases from the Hellenic population across six NLRP3 inflammasome pathway genes. Results: Three common CARD8 variants confer decreased risk for DN, namely rs11665831 (OR = 0.62, p = 0.016), rs11083925 (OR = 0.65, p = 0.021), and rs2043211 (OR = 0.66, p = 0.026), independent of sex or co-inheritance with an IL-1B variant. Conclusion: CARD8 acts as an NLRP3, NF-κB and caspase-1 inhibitor; perhaps, alterations in the cross-talk between CARD8, NF-κB, and NLRP3, which could affect the pro-inflammatory environment in T2DM, render diabetic carriers of certain common CARD8 variants potentially less likely to develop T2DM-related pro-inflammatory responses followed by DN. These preliminary, yet novel, observations will require validation in larger cohorts from several ethnic groups.

BackgroundMyasthenia Gravis (MG) is a rare autoimmune disorder affecting the neuromuscular junction. Here, we investigate the genetic architecture of MG performing a genomewide association study (GWAS) of the largest MG dataset analyzed to date.MethodsWe integrated GWAS from three different datasets (1,401 cases, 3,508 controls) and performed MG GWAS and onset-specific analyses. We also carried out HLA fine-mapping, gene-based, gene ontology and tissue enrichment analyses and investigated genetic correlation to other autoimmune disorders.FindingsWe observed the strongest MG association to TNFRSF11A (rs4369774, p=1.09×10−13; OR=1.4). Gene-based analysis revealed AGRN as a novel MG susceptibility gene. HLA fine-mapping pointed to two independent loci significantly associated with MG: HLA-DRB1 (with a protective role) and HLA-B. MG onset-specific analysis, reveals differences in the genetic architecture of Early-Onset vs Late-Onset MG. Furthermore, we find MG to be genetically correlated with Type 1 Diabetes, Rheumatoid Arthritis and late-onset Vitiligo.InterpretationOverall, our results are consistent with previous studies highlighting the role of the HLA and TNFRSF11A in MG etiology and different risk genes in EOMG vs LOMG. Furthermore, our gene-based analysis implicates, for the first time, AGRN as a MG susceptibility locus. AGRN encodes agrin, which is involved in neuromuscular junction formation. Mutations in AGRN have been found to underlie congenital myasthenic syndrome. Gene ontology analysis suggests an intriguing role for symbiotic processes in MG etiology. We also uncover genetic correlation of MG to Type 1 Diabetes, Rheumatoid Arthritis and late-onset Vitiligo, pointing to shared underlying genetic mechanisms.FundingThis work was supported by NSF award #1715202, the European Social Fund and Greek funds through the National Strategic Reference Framework (NSRF) THALES Programme 2012–2015 and the NSRF ARISTEIA II Programme 2007–2013 to PP, and grants from the Association Francaise contre les Myopathies (AFM, Grant No. 80077) to ST.Research in contextEvidence before this studyMyasthenia Gravis (MG) is a complex disease caused by the interaction of genetic and environmental factors that lead to autoimmune activation. Previous studies have shown that the human leukocyte antigen (HLA) displays the most robust genetic association signals to MG. Additional susceptibility genes that have emerged through genomewide association studies (GWAS), include CTLA4 and TNFRSF11A. Previous studies also support the hypothesis of distinct risk loci underlying Early-Onset versus Late-Onset MG subgroups (EOMG vs LOMG). For instance, PTPN22 and TNIP1 genes have been implicated in EOMG and ZBTB10 in LOMG. In the GWAS studies published so far, HLA and TNFRSF11A associations appear to be confirmed; however, the association of other implicated genes still requires replication.Added value of this studyWe present the largest GWAS for MG to date, integrating three different datasets. We identify AGRN as a novel MG risk locus and replicate previously reported susceptibility loci, including HLA, TNFRSF11A, and CTLA4. Our analysis also supports the existence of a different genetic architecture in EOMG vs LOMG and identifies a region between SRCAP and FBRS as a novel EOMG risk locus. Additionally, through HLA fine-mapping, we observe different HLA genes implicated in EOMG vs LOMG (HLA-B and HLA-DRB1 respectively). Finally, we detect positive genetic correlation of MG with other autoimmune disorders including Type 1 Diabetes, Rheumatoid Arthritis, and late-onset Vitiligo, suggesting a shared genetic basis across them.Implications of all the available evidenceOur study sheds light into the etiology of MG identifying AGRN as a novel risk locus. AGRN encodes agrin, a protein with a significant role in the formation of the neuromuscular junction and mutations in this gene have been associated with congenital myasthenic syndrome. Our findings hint to an intriguing hypothesis of symbiotic processes underlying MG pathogenesis and points to muscle growth and development in EOMG and steroid hormones synthesis in LOMG. The observed genetic correlations between MG and certain other autoimmune disorders could possibly underlie comorbidity patterns across this group of disorders.

Soluble epoxide hydrolase 2 (EPHX2) is an enzyme promoting increased cellular apoptosis through induction of oxidative stress (OS) and inflammation. The EPHX2 gene which encodes soluble EPHX2 might be implicated in the pathogenesis and development of OS and atherosclerosis. We aimed to assess the possible association between two functional polymorphisms of the EPHX2 gene (rs2741335 and rs11780592) with oxidized LDL (ox-LDL), carotid atherosclerosis, mortality, and cardiovascular (CV) disease in 118 patients with diabetic chronic kidney disease (CKD). At baseline, ox-LDL and carotid intima-media thickness (cIMT) were evaluated and all patients were followed for seven years with outcomes all-cause mortality and CV events. rs11780592 EPHX2 polymorphism was associated with ox-LDL, cIMT, albuminuria, and hypertension. Compared to AG and GG, AA homozygotes had higher values of albuminuria, ox-LDL, and cIMT ( p = 0.046 , p = 0.003 , and p = 0.038 , respectively). These associations remained significant, even after grouping for the G allele. After the follow-up period, 42/118 patients died (30/60 with AA genotype, 11/42 with AG genotype, and 1/12 with GG genotype) and 49/118 experienced a new CV event (fatal or nonfatal). The Kaplan-Meier analysis revealed that patients with the AA genotype exhibited a significantly higher mortality risk, compared to patients with AG and GG genotypes ( p = 0.006 ). This association became even stronger, when AG and GG genotypes were grouped (AA vs. AG/GG, p = 0.002 ). AA homozygotes were strongly associated with all-cause mortality in both univariate (hazard ratio HR = 2.74 , confidence interval CI = 1.40 – 5.35 , p = 0.003 ) and multivariate Cox regression analysis ( HR = 2.61 , CI = 1.32 – 5.17 , p = 0.006 ). In conclusion, our study demonstrated that genetic variations of EPHX2 gene were associated with increased circulating ox-LDL, increased cIMT, and all-cause mortality in diabetic CKD. Since EPHX2 regulates the cholesterol efflux and the oxidation of LDL in foam cells and macrophages, our study suggests that a genetic basis to endothelial dysfunction and OS might be present in diabetic CKD.

SUMMARY We previously established the contribution of de novo damaging sequence variants to Tourette disorder (TD) through whole-exome sequencing of 511 trios. Here, we sequence an additional 291 TD trios and analyze the combined set of 802 trios. We observe an overrepresentation of de novo damaging variants in simplex, but not multiplex, families; we identify a high-confidence TD risk gene, CELSR3 (cadherin EGF LAG seven-pass G-type receptor 3); we find that the genes mutated in TD patients are enriched for those related to cell polarity, suggesting a common pathway underlying pathobiology; and we confirm a statistically significant excess of de novo copy number variants in TD. Finally, we identify significant overlap of de novo sequence variants between TD and obsessive-compulsive disorder and de novo copy number variants between TD and autism spectrum disorder, consistent with shared genetic risk., In Brief Wang et al. expand their earlier exome-sequencing work in TD, adding 291 trios and conducting combined analyses suggesting de novo variants carry more risk in individuals with unaffected parents, establishing de novo structural variants as risk factors, identifying CELSR3 as a risk gene, and implicating cell polarity in pathogenesis., Graphical Abstract

Cardiovascular (CV) events are the first cause of death in patients with chronic renal disease (CKD) and in patients with type 2 diabetes mellitus (DM2). The combination of CKD and DM2 elevates the risk of both cardiovascular disease (CVD) and death in this high-risk population. Besides traditional risk factors, such as dyslipidemia, smoking, obesity, and carotid atherosclerosis, novel factors are under investigation such as genetic polymorphisms. Lipoxygenases (LOXs) and their genes are of critical importance in oxidative stress, inflammation, and atherosclerosis. The aim of the study is to clarify a potential ALOX12 role in CVD presence and progress of diabetic patients in different stages of nephropathy. We studied 145 patients with a documented history of DM2 for at least 10 years and diabetic nephropathy (DN), mean age 68 ± 9 years, body mass index 31 ± 5 kg/m2, and different stages of renal disease, depending on glomerular filtration rate. The sample population consisted of two groups: 108 DM2 patients with DN in all five stages of CKD and 37 DM2 patients as controls. Anthropometric and clinical characteristics, interview for history of previous CV event, and assessment of carotid intima-media thickness (cIMT) were recorded at baseline. All patients were genotyped for ALOX12 polymorphisms with focus on rs14309. Genotypes (AA, AG, and GG) were evaluated for any possible role in CVD, and grouping was performed on A genotype, which is the dominant model. All participants were followed over a period of 7 years, and the end points studied were all-cause mortality, CV mortality, and CV events. CV events were defined as myocardial infarction (MI), stroke, or peripheral artery disease. The GG genotype has been significantly associated with cIMT levels above 0.86 mm and with history of MI. Regarding the presence of an atherosclerotic plaque in either carotid artery, no significant association was found when the genotypes were assessed on their own. After grouping, though, GG genotype revealed a significant association between carotid plaque formation and atheromatosis. Kaplan–Meier analysis revealed that ALOX12 gene GG genotype predicted all-cause mortality, CV mortality, and CV events. Similarly, when AA and AG genotypes were grouped, Kaplan–Meier analysis showed that patients with GG genotype presented an even more significant higher all-cause mortality, CV mortality, and CV events compared with AA and AG genotypes combined. After adjustment for several traditional risk factors, multivariate Cox proportional hazard analysis showed that patients with the GG genotype had a significant higher risk of all-cause mortality, a threefold increase in CV mortality, and a twofold increased risk for CV events compared to patients with the AA or the AG genotype. ALOX12 rs14309 GG genotype expression was found to be significantly associated with MI, higher cIMT, increased CV events, CV, and overall mortality. This phenomenon could be partially explained by the increased platelet proaggregatory activity of AA products and the control they exert in thrombotic occurrence and plaque formation.

Accumulating evidence suggests a potential implication of vitamin D biological network in the pathogenesis of diabetes mellitus. The megalin-cubilin endocytotic system constitutes a key transport structure, with a modulating role in vitamin D metabolism. We aimed to assess the contribution of variants in the CUBN gene to the genetic risk of Type 2 Diabetes Mellitus (T2DM). 95 polymorphisms within CUBN were genotyped in 716 patients with T2DM and 542 controls of Greek origin. Samples were analyzed on Illumina Human PsychArray. Permutation test analysis was implemented to determine statistical significance. Twenty-five-hydroxy-vitamin-D [25(OH)D)] levels were measured in a sub-group of participants (n = 276). Permutation analysis associated rs11254375_G/T (pemp = 0.00049, OR = 1.482), rs6602175_G/T (pemp = 0.016, OR = 0.822), rs1801224_G/T (pemp = 0.025, OR = 0.830), rs4366393_A/G (pemp = 0.028, OR = 0.829) and rs7071576_A/G (pemp = 0.04, OR = 1.219) with T2DM. Mean 25(OH)D concentrations were significantly lower in patients with T2DM compared to controls (16.70 ± 6.69 ng/ml vs 18.51 ± 6.71 ng/ml, p

The EMTICS collaborative group: Anastasiou, Zacharias; Apter, Alan; Baglioni, Valentina; Bartolini, Erika; Benaroya-Milshtein, Noa; Bodmer, Benjamin; Bognar, Emese; Burger', Bianka; Buttiglione, Maura; Cardona, Francesco; Vela, Marta Correa; Creti, Roberta; Dietrich, Andrea; Debes, Nanette M.; Efstratiou, Androulla; Ferro, Maria Cristina; Fremer, Carolin; Garcia-Delgar, Blanca; Gariup, Maria; Georgitsi, Marianthi; Gulisano, Mariangela; Hagen, Annelieke; Hagstrom, Julie; Hedderly, Tammy J.; Heyman, Isobel; Hoekstra, Pieter J.; Huyser, Chaim; Imperi, Monica; Karagiannidis, Iordanis; Laviola, Giovanni; Macri, Simone; Madruga-Garrido, Marcos; Margarit, Immaculada; Marotta, Anna; Martino, Davide; Meier, Ute C.; Mir, Pablo; Mo, Natalie; More, Astrid; Mueller-Vahl, Kirsten; Muenchau, Alexander; Nagy, Peter; Neri, Valeria; Openneer, Thafra J. C.; Orefici, Graziella; Paschou, Peristera; Pellico, Alessandra; Petruzzelli, Onofrio; Porcelli, Cesare; Redondo, Marina; Rizzo, Renata; Roazzi, Paolo; Roessner, Veit; Ruhrman, Daphna; Schnell, Jaana M. L.; Schrag, Anette; Schutze, Gregor A.; Schwarz, Markus J.; Silvestri, Paola Rosaria; Skov, Liselotte; Steinberg, Tamar; Stober, Sara; Tallon, Marco; Tarnok, Zsanett, In Tourette Syndrome (TS) a role for autoantibodies directed against neuronal proteins has long been suspected, but so far results are still inconsistent. The aim of this study was to look for antibodies to specific or undefined neuronal proteins that could be involved in the aetiology of the disease. Sera from children with Tourette Syndrome or another chronic tic disorder (TS/TD), collected as part of the longitudinal European Multicenter Tics in Children Study, were investigated. Participants included 30 siblings of patients with TS/TD prior to developing tics (preclinical stage) and the same children after the first tic onset (onset), and 158 patients in the chronic phase undergoing an acute relapse (exacerbation). Presence of antibodies binding to rodent brain tissue was assessed by immunohistology on rat brain sections and by immunofluorescent staining of live hippocampal neurons. Live cell-based assays were used to screen for antibodies to NMDAR, CASPR2, LGI1, AMPAR and GABAAR. Immunohistology indicated evidence of antibodies reactive with brain tissue, binding mainly to the hippocampus, the basal ganglia or the cerebellum in 26/218 (12%), with 8% of the preclinical or onset sera binding to the dentate gyrus/CA3 region or cerebellum. Only two individuals (one pre-clinical, one chronic) had antibodies binding the NMDAR and the binding was only weakly positive. No other specific antibodies were detected. Despite some immunoreactivity towards neuronal antigens on brain tissue, this was not mirrored by antibodies binding to live neurons, suggesting the presence of non-specific antibodies or those that bind non-pathogenic intracellular epitopes. NMDAR or the other neuronal surface antibodies tested were very infrequent in these patients. The evidence for pathogenic antibodies that could be causative of TS is weak.

Purpose of Review Gilles de la Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder characterized by multiple motor and vocal tics, commonly associated with attention deficit hyperactivity disorder (ADHD), obsessive–compulsive disorder (OCD) and autism spectrum disorders (ASDs). Here, we summarize and discuss evidence pointing to a shared genetic basis among TS, OCD, ADHD and ASD.

Background: Approximately one third of type 2 diabetes mellitus (T2DM) cases present with diabetic nephropathy (DN), the leading cause of end-stage renal disease. Inflammation plays an important role in T2DM disease and DN pathogenesis. NLRP3 inflammasomes are complexes that regulate interleukin-1B (IL-1B) and IL-18 secretion, both involved in inflammatory responses. Activation of NLRP3 is associated with DN onset and progression. Here, we explore whether DN is associated with variants in genes encoding key members of the NLRP3 inflammasome pathway. Methods: Using genome-wide association data, we performed a pilot case-control association study, between 101 DN-T2DM and 185 non-DN-T2DM cases from the Hellenic population across six NLRP3 inflammasome pathway genes. Results: Three common CARD8 variants confer decreased risk for DN, namely rs11665831 (OR = 0.62, p = 0.016), rs11083925 (OR = 0.65, p = 0.021), and rs2043211 (OR = 0.66, p = 0.026), independent of sex or co-inheritance with an IL-1B variant. Conclusion: CARD8 acts as an NLRP3, NF-κB and caspase-1 inhibitor; perhaps, alterations in the cross-talk between CARD8, NF-κB, and NLRP3, which could affect the pro-inflammatory environment in T2DM, render diabetic carriers of certain common CARD8 variants potentially less likely to develop T2DM-related pro-inflammatory responses followed by DN. These preliminary, yet novel, observations will require validation in larger cohorts from several ethnic groups.

Purpose Understanding the healthy brain aging process is key to uncover the mechanisms that lead to pathologic age-related neurodegeneration, including progression to Alzheimer disease (AD). We aimed to address the issue of pathologic heterogeneity that often underlies a clinical AD diagnosis. Methods We performed a deep whole-genome sequencing study aiming to identify variants that are associated specifically with healthy brain aging. Patients We examined samples from the community-based longitudinal Vienna Transdanubian Aging study comparing neuropathologically "healthy" aging in individuals above 80 years of age with pure AD patients of the same age. Results Focusing on potentially functional variants, we discovered a single variant (rs10149146) that lies on the autophagy-associated TECPR2 gene and was carried by 53.6% of the "healthy" brain elderly individuals (15/28). An additional nonsynonymous variant on the CINP gene (encoding a cell cycle checkpoint protein) was also found in 46% of healthy controls. Both variants are absent from all AD cases. TECPR2 and CINP appear to be "partner" genes in terms of regulation and their associated transcription factors have been previously implicated in AD and neurodegeneration. Conclusions Our study underlines the strength of neuropathology-driven definitions in genetic association studies and points to a potentially neuroprotective effect of key molecules of autophagy and cell cycle control.

Background: Inflammation plays a pivotal role in the pathogenesis of diabetes and its complications. Arachidonic acid lipoxygenases have been intensively studied in their role in inflammation in metabolic pathways. Thus, we aimed to explore variants of lipoxygenase genes (arachidonate lipoxygenase genes) in a diabetes adult population using a case-control study design. Methods: Study population consisted of 1285 elderly participants, 716 of whom had type 2 diabetes mellitus. The control group consisted of non-diabetes individuals with no history of diabetes history and with a glycated haemoglobin Results: Our findings showed an association of rs9669952 (odds ratio = 0.738, p = 0.013) and rs1132340 (odds ratio = 0.652, p = 0.008) in ALOX5AP and rs11239524 in ALOX5 gene with disease (odds ratio = 0.808, p = 0.038). Rs9315029 which is located near arachidonate ALOX5AP also associated with type 2 diabetes mellitus ( p = 0.025). No variant of ALOX12 and ALOX15 genes associated with disease. Conclusion: These results indicate a potential protective role of ALOX5AP and 5-arachidonate lipoxygenase gene in diabetes pathogenesis, indicating further the importance of the relationship between diabetes and inflammation. Larger population studies are required to replicate our findings.

Understanding the healthy brain aging process is key to uncovering the mechanisms leading to pathological age-related neurodegeneration, including progression to Alzheimer’s disease (AD). Here, we report the first deep whole genome sequencing study aiming to identify variants that are associated specifically to healthy brain aging defined on both clinical and neuropathological level, thus tacking the issue of pathological heterogeneity that often underlies a clinical AD diagnosis. We studied samples from the VITA brain bank and followed an extreme phenotypic ends study design comparing neuropathologically “healthy” aging individuals above 80 years of age with pure AD patients of the same age. Focusing on the extreme ends of the phenotypic distribution, and potentially functional variants, we discover a single variant (rs10149146) carried by 53.6% of the “healthy” brain elderly individuals in our study (15/28 individuals) and none of the 12 AD cases. This variant lies on the autophagy and cell cycle associated TECPR2 gene. Autophagy dysfunction has been previously implicated in multiple progressive neurodegenerative diseases. An additional non-synonymous variant on the CINP gene (encoding a cell-cycle checkpoint protein) is also found in 46% of healthy controls and absent from all the AD cases. TECPR2 and CINP appear to be “partner” genes in terms of regulation and their associated transcription factors have been previously implicated in AD and neurodegeneration. Our study is the first to support the hypothesis that a TECPR2 non-synonymous variant carries a significant neuroprotective effect pointing to key molecules for the involvement of autophagy and cell cycle control in protection from neurodegeneration.

Background: The increasing volume and complexity of high-throughput genomic data make analysis and prioritization of variants difficult for researchers with limited bioinformatics skills. Variant Ranker allows researchers to rank identified variants and determine the most confident variants for experimental validation.Results: We describe Variant Ranker, a user-friendly simple web-based tool for ranking, filtering and annotation of coding and non-coding variants. Variant Ranker facilitates the identification of causal variants based on novelty, effect and annotation information. The algorithm implements and aggregates multiple prediction algorithm scores, conservation scores, allelic frequencies, clinical information and additional open-source annotations using accessible databases via ANNOVAR. The available information for a variant is transformed into user-specified weights, which are in turn encoded into the ranking algorithm. Through its different modules, users can (i) rank a list of variants (ii) perform genotype filtering for case-control samples (iii) filter large amounts of high-throughput data based on user custom filter requirements and apply different models of inheritance (iv) perform downstream functional enrichment analysis through network visualization. Using networks, users can identify clusters of genes that belong to multiple ontology categories (like pathways, gene ontology, disease categories) and therefore expedite scientific discoveries. We demonstrate the utility of Variant Ranker to identify causal genes using real and synthetic datasets. Our results indicate that Variant Ranker exhibits excellent performance by correctly identifying and ranking the candidate genesConclusions: Variant Ranker is a freely available web server on http://paschou-lab.mbg.duth.gr/Software.html. This tool will enable users to prioritise potentially causal variants and is applicable to a wide range of sequencing data.

We developed a series of interrelated locus-specific databases to store all published and unpublished genetic variation related to these disorders, and then implemented microattribution to encourage submission of unpublished observations of genetic variation to these public repositories 1. A total of 1,941 unique genetic variants in 37 genes, encoding globins (HBA2, HBA1, HBG2, HBG1, HBD, HBB) and other erythroid proteins (ALOX5AP, AQP9, ARG2, ASS1, ATRX, BCL11A, CNTNAP2, CSNK2A1, EPAS1, ERCC2, FLT1, GATA1, GPM6B, HAO2, HBS1L, KDR, KL, KLF1, MAP2K1, MAP3K5, MAP3K7, MYB, NOS1, NOS2, NOS3, NOX3, NUP133, PDE7B, SMAD3, SMAD6, and TOX) are currently documented in these databases with reciprocal attribution of microcitations to data contributors. Our project provides the first example of implementing microattribution to incentivise submission of all known genetic variation in a defined system. It has demonstrably increased the reporting of human variants and now provides a comprehensive online resource for systematically describing human genetic variation in the globin genes and other genes contributing to hemoglobinopathies and thalassemias. The large repository of previously reported data, together with more recent data, acquired by microattribution, demonstrates how the comprehensive documentation of human variation will provide key insights into normal biological processes and how these are perturbed in human genetic disease. Using the microattribution process set out here, datasets which took decades to accumulate for the globin genes could be assembled rapidly for other genes and disease systems. The principles established here for the globin gene system will serve as a model for other systems and the analysis of other common and/or complex human genetic diseases.

Aim: TPMT activity is characterized by a trimodal distribution, namely low, intermediate and high methylator. TPMT gene promoter contains a variable number of GC-rich tandem repeats (VNTRs), namely A, B and C, ranging from three to nine repeats in length in an AnBmC architecture. We have previously shown that the VNTR architecture in the TPMT gene promoter affects TPMT gene transcription. Materials, methods & results: Here we demonstrate, using reporter assays, that 6-mercaptopurine (6-MP) treatment results in a VNTR architecture-dependent decrease of TPMT gene transcription, mediated by the binding of newly recruited protein complexes to the TPMT gene promoter, upon 6-MP treatment. We also show that acute lymphoblastic leukemia patients undergoing 6-MP treatment display a VNTR architecture-dependent response to 6-MP. Conclusion: These data suggest that the TPMT gene promoter VNTR architecture can be potentially used as a pharmacogenomic marker to predict toxicity due to 6-MP treatment in acute lymphoblastic leukemia patients. Original submitted 27 July 2011; Revision submitted 24 October 2011

The rs2071348 (g.5264146A>C) polymorphism on the HBB pseudogene, namely HBBP1, previously emerged as a variant significantly associated with a milder disease phenotype in Asian β(0)-thalassemia/hemoglobin (Hb) E (β(0)-thal/Hb E [β26(B8)Glu→Lys, GAG>AAG]) patients. In this study, we aimed to explore the possible association of rs2071348 with β-thalassemia (β-thal) disease severity in a group of β-thal major (β-TM) patients (severe phenotype) and β-thal intermedia (β-TI) patients (mild phenotype) of Hellenic origin and compare the results with normal (non thalassemic) individuals of the same origin. In addition, we explored whether this single nucleotide polymorphism (SNP) can be exploited as a pharmacogenomic marker to predict the outcome of Hb F-augmenting therapy in β-thal patients receiving hydroxyurea (HU). Our data suggest that the rs2071348 polymorphism is associated with higher Hb F levels and a milder β-thal disease phenotype. However, the rs2071348 polymorphism in the HBBP1 gene does not correlate with response to HU treatment.

National/ethnic mutation databases aim to document the genetic heterogeneity in various populations and ethnic groups worldwide. We have previously reported the development and upgrade of FINDbase (www.findbase.org), a database recording causative mutations and pharmacogenomic marker allele frequencies in various populations around the globe. Although this database has recently been upgraded, we continuously try to enhance its functionality by providing more advanced visualization tools that would further assist effective data querying and comparisons. We are currently experimenting in various visualization techniques on the existing FINDbase causative mutation data collection aiming to provide a dynamic research tool for the worldwide scientific community. We have developed an interactive web-based application for population-based mutation data retrieval. It supports sophisticated data exploration allowing users to apply advanced filtering criteria upon a set of multiple views of the underlying data collection and enables browsing the relationships between individual datasets in a novel and meaningful way.

Aims: Population and ethnic group-specific allele frequencies of pharmacogenomic markers are poorly documented and not systematically collected in structured data repositories. We developed the Frequency of Inherited Disorders Pharmacogenomics database (FINDbase-PGx), a separate module of the FINDbase, aiming to systematically document pharmacogenomic allele frequencies in various populations and ethnic groups worldwide. Materials & methods: We critically collected and curated 214 scientific articles reporting pharmacogenomic markers allele frequencies in various populations and ethnic groups worldwide. Subsequently, in order to host the curated data, support data visualization and data mining, we developed a website application, utilizing Microsoft™ PivotViewer software. Results: Curated allelic frequency data pertaining to 144 pharmacogenomic markers across 14 genes, representing approximately 87,000 individuals from 150 populations worldwide, are currently included in FINDbase-PGx. A user-friendly query interface allows for easy data querying, based on numerous content criteria, such as population, ethnic group, geographical region, gene, drug and rare allele frequency. Conclusion: FINDbase-PGx is a comprehensive database, which, unlike other pharmacogenomic knowledgebases, fulfills the much needed requirement to systematically document pharmacogenomic allelic frequencies in various populations and ethnic groups worldwide.

Interindividual variable drug response is correlated with sequence alterations in genes encoding drug-metabolizing enzymes and transporters, affecting drug absorption, distribution, metabolism and excretion. This variable drug response may have an impact on disease therapeutic outcomes, tolerance to adverse drug reactions and even survival. Sequence alterations may occur not only within the coding region of a gene, but in its regulatory elements too, affecting gene transcription and gene-expression levels. Here, we provide a compilation of the current knowledge of pharmacogenomics related to transcription, with a focus on the effect of SNPs and short tandem repeats residing in cis-regulatory elements of 11 genes encoding for drug-metabolizing enzymes and drug transporters. In addition, we comment on two genes encoding enzymes that are drug targets themselves. Finally, we briefly discuss the currently available methodologies for clinically assessing pharmacogenomic profiles, which could potentially in the future facilitate drug treatment-individualization via the identification of molecular signatures in specific patient groups.

Mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene have been shown to predispose to pituitary adenoma predisposition, a condition characterized by growth hormone (GH)-secreting pituitary tumors. To study AIP-mediated tumorigenesis, we generated an Aip mouse model. Heterozygous mice developed normally but were prone to pituitary adenomas, in particular to those secreting GH. A complete loss of AIP was detected in these lesions, and full penetrance was reached at the age of 15 months. No excess of any other tumor type was found. Ki-67 analysis indicated that Aip-deficient tumors have higher proliferation rates compared with Aip-proficient tumors, suggesting a more aggressive disease. Similar to human AIP-deficient pituitary adenomas, immunohistochemical studies showed that expression of aryl hydrocarbon receptor nuclear translocator 1 or 2 (ARNT or ARNT2) protein was lost in the mouse tumors, suggesting that mechanisms of AIP-related tumorigenesis involve aberrant ARNT function. The Aip(+/-) mouse appears to be an excellent model for the respective human disease phenotype. This model constitutes a tool to further study AIP-associated pituitary tumorigenesis and may be potentially valuable in efforts to develop therapeutic strategies to treat pituitary adenomas.

Objectives: Homologous recombination is a frequent phenomenon in multigene families and as such it occurs several times in both the α- and β-like globin gene families. In numerous occasions, genetic recombination has been previously implicated as a major mechanism that drives mutagenesis in the human globin gene clusters, either in the form of unequal crossover or gene conversion. Unequal crossover results in the increase or decrease of the human globin gene copies, accompanied in the majority of cases with minor phenotypic consequences, while gene conversion contributes either to maintaining sequence homogeneity or generating sequence diversity. The role of genetic recombination, particularly gene conversion in the evolution of the human globin gene families has been discussed elsewhere. Conclusion: Here, we summarize our current knowledge and review existing experimental evidence outlining the role of genetic recombination in the mutagenic process in the human globin gene families.

ObjectiveMutations in the aryl hydrocarbon receptor-interacting protein (AIP) were recently shown to confer a pituitary adenoma predisposition in patients with familial isolated pituitary adenomas (FIPA). We report a large Samoan FIPA kindred from Australia/New Zealand with an R271W mutation that was associated with aggressive pituitary tumors.Design and methodsCase series with germline screening of AIP and haplotype analyses among R271W families.ResultsThis previously unreported kindred consisted of three affected individuals that either presented with or had first symptoms of a pituitary macroadenoma in late childhood or adolescence. The index case, a 15-year-old male with incipient gigantism and his maternal aunt, had somatotropinomas, and the maternal uncle of the index case had a prolactinoma. All tumors were large (15, 40, and 60 mm maximum diameter) and two required transcranial surgery and radiotherapy. All three affected subjects and ten other unaffected relatives were found to be positive for a germline R271W AIP mutation. Comparison of the single nucleotide polymorphism patterns among this family and two previously reported European FIPA families with the same R271W mutation demonstrated no common ancestry.ConclusionsThis kindred exemplifies the aggressive features of pituitary adenomas associated with AIP mutations, while genetic analyses among three R271W FIPA families indicate that R271W represents a mutational hotspot that should be studied further in functional studies.

Objective: Primary hyperparathyroidism (PHPT), a common endocrine condition, is usually caused by sporadically occurring parathyroid adenoma. A subset of patients carry germline mutations in genes such as MEN1 (multiple endocrine neoplasia type 1), HRPT2 (hyperparathyroidism 2), and CASR (calcium-sensing receptor) predisposing to syndromic forms of PHPT or familial isolated hyperparathyroidism (FIHP). Recently, germline mutations in two novel genes AIP (aryl hydrocarbon receptor-interacting protein) and CDKN1B (cyclin-dependent kinase inhibitor 1B) have been found to be associated with endocrine tumors. The purpose of this study was to evaluate the role of MEN1, HRPT2, CASR, AIP, and CDKN1B genes in PHPT patients with clinical features suggestive of genetic predisposition. Patients and design: Medical records of patients treated for PHPT from 1974 to 2001 at Oulu University Hospital were reviewed. Patients with multiglandular or recurrent/persistent disease, other MEN1-related manifestations, aged 40 yr or younger at onset or with a family history of PHPT/MEN1-related tumor were invited to the study. Twenty patients with previously diagnosed MEN1 were excluded. Participants were interviewed and blood samples obtained for biochemical screening and mutation analysis of MEN1, HRPT2, CASR, AIP, and CDKN1B. Results: Of the 56 invited patients, 29 took part in the study. One patient was found to carry the c. 1356_1367del12 MEN1 founder mutation. Mutations in other genes were not detected. Conclusions: Apart from MEN1, mutations in other genes predisposing to PHPT seem to be rare or non-existing in Northern Finnish PHPT patients. No evidence was found for a role of AIP or CDKN1B in PHPT predisposition.

Pituitary adenomas are common neoplasms of the anterior pituitary gland. Germ-line mutations in the aryl hydrocarbon receptor-interacting protein ( AIP ) gene cause pituitary adenoma predisposition (PAP), a recent discovery based on genetic studies in Northern Finland. In this population, a founder mutation explained a significant proportion of all acromegaly cases. Typically, PAP patients were of a young age at diagnosis but did not display a strong family history of pituitary adenomas. To evaluate the role of AIP in pituitary adenoma susceptibility in other populations and to gain insight into patient selection for molecular screening of the condition, we investigated the possible contribution of AIP mutations in pituitary tumorigenesis in patients from Europe and the United States. A total of 460 patients were investigated by AIP sequencing: young acromegaly patients, unselected acromegaly patients, unselected pituitary adenoma patients, and endocrine neoplasia-predisposition patients who were negative for MEN1 mutations. Nine AIP mutations were identified. Because many of the patients displayed no family history of pituitary adenomas, detection of the condition appears challenging. Feasibility of AIP immunohistochemistry (IHC) as a prescreening tool was tested in 50 adenomas: 12 AIP mutation-positive versus 38 mutation-negative pituitary tumors. AIP IHC staining levels proved to be a useful predictor of AIP status, with 75% sensitivity and 95% specificity for germ-line mutations. AIP contributes to PAP in all studied populations. AIP IHC, followed by genetic counseling and possible AIP mutation analysis in IHC-negative cases, a procedure similar to the diagnostics of the Lynch syndrome, appears feasible in identification of PAP.

Germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene were recently identified in individuals with pituitary adenoma predisposition (PAP). These patients have prolactin (PRL) or growth hormone (GH) oversecreting pituitary adenomas, the latter exhibiting acromegaly or gigantism. Loss-of-heterozygosity (LOH) analysis revealed that AIP is lost in PAP tumours, suggesting that it acts as a tumour-suppressor gene. Aryl hydrocarbon receptor interacting protein is involved in several pathways, but it is best characterised as a cytoplasmic partner of the aryl hydrocarbon receptor (AHR). To examine the possible role of AIP in the genesis of common cancers, we performed somatic mutation screening in a series of 373 colorectal cancers (CRCs), 82 breast cancers, and 44 prostate tumour samples. A missense R16H (47G>A) change was identified in two CRC samples, as well as in the respective normal tissues, but was absent in 209 healthy controls. The remaining findings were silent, previously unreported, changes of the coding, non-coding, or untranslated regions of AIP. These results suggest that somatic AIP mutations are not common in CRC, breast, and prostate cancers.

Context: Germline mutations in the MEN1 gene predispose to multiple endocrine neoplasia type 1 (MEN1) syndrome, but in up to 20–25% of clinical MEN1 cases, no MEN1 mutations can be found. Recently, a germline mutation in the CDKN1B gene, encoding p27Kip1, was reported in one suspected MEN1 family with two acromegalic patients. Objective: Our objective was to evaluate the role of CDKN1B/p27Kip1 in human tumor predisposition in patients clinically suspected of MEN1 but testing negative for MEN1 germline mutation as well as in familial and sporadic acromegaly/pituitary adenoma patients. Design: Genomic DNA was analyzed for germline mutations in the CDKN1B/p27Kip1 gene by PCR amplification and direct sequencing. Setting: The study was conducted at nonprofit academic research and medical centers. Patients: Thirty-six Dutch and one German suspected MEN1 patient, who previously tested negative for germline MEN1 gene mutations, were analyzed. In addition, 19 familial and 50 sporadic acromegaly/pituitary adenoma patients from Europe and the United States were included in the study. Main Outcome Measures: We analyzed germline CDKN1B/p27Kip1 mutations in individuals with pituitary adenoma and MEN1-like features. Results: A heterozygous 19-bp duplication (c.59_77dup19) leading to a truncated protein product was identified in one Dutch patient with suspected MEN1 phenotype, pituitary adenoma, carcinoid tumor, and hyperparathyroidism (one of 36, 2.8%). No mutations were detected in either familial or sporadic acromegaly/pituitary adenoma patients. Conclusions: Our results support the previous finding that germline CDKN1B/p27Kip1 mutations predispose to a human MEN1-like condition. However, such mutations appear uncommon in suspected MEN1 cases and rare or nonexistent in familial or sporadic acromegaly/pituitary adenoma patients.

Pituitary adenomas are common in the general population, and understanding their molecular basis is of great interest. Combining chip-based technologies with genealogy data, we identified germline mutations in the aryl hydrocarbon receptor interacting protein ( AIP ) gene in individuals with pituitary adenoma predisposition (PAP). AIP acts in cytoplasmic retention of the latent form of the aryl hydrocarbon receptor and also has other functions. In a population-based series from Northern Finland, two AIP mutations account for 16% of all patients diagnosed with pituitary adenomas secreting growth hormone and for 40% of the subset of patients who were diagnosed when they were younger than 35 years of age. Typically, PAP patients do not display a strong family history of pituitary adenoma; thus, AIP is an example of a low-penetrance tumor susceptibility gene.

Aim: In this study we explored the association between genetic variations in MAP3K5 and PDE7B genes, residing on chromosome 6q23, and disease severity in β-hemoglobinopathy patients, as well as the association between these variants with response to hydroxyurea (HU) treatment. Furthermore, we examined MAP3K5 expression in the context of high fetal hemoglobin (HbF) and upon HU treatment in erythroid progenitor cells from healthy and KLF1 haploinsufficient individuals. Materials & methods: For this purpose, we genotyped β-thalassemia intermedia and major patients and healthy controls, as well as a cohort of compound heterozygous sickle cell disease/β-thalassemia patients receiving HU as HbF augmentation treatment. Furthermore, we examined MAP3K5 expression in the context of high HbF and upon HU treatment in erythroid progenitor cells from healthy and KLF1 haploinsufficient individuals. Results: A short tandem repeat in the MAP3K5 promoter and two intronic MAP3K5 gene variants, as well as a PDE7B variant, are associated with low HbF levels and a severe disease phenotype. Moreover, MAP3K5 mRNA expression levels are altered in the context of high HbF and are affected by the presence of HU. Lastly, the abovementioned MAP3K5 variants are associated with HU treatment efficacy. Conclusion: Our data suggest that these MAP3K5 variants are indicative of β-thalassemia disease severity and response to HU treatment. Original submitted 24 September 2012; Revision submitted 4 February 2013

Pharmacogenomics studies how the variations of the individuals' genetic makeup are correlated with a person's response to certain drugs in relation to the therapeutic efficiency, clinical outcome, or even survival, and how they affect drug metabolism, transport, or clearance. Yet, since the incidence of these polymorphisms, being either single-point variations or small insertions/deletions, varies among different populations, a systematic collection and documentation of these variations is warranted, in order to facilitate implementation of pharmacogenomics in different populations. Here we review the existing electronic databases related to pharmacogenomics and pay particular attention in the description of the pharmacogenomics module Frequency of Inherited Disorders database (FINDbase), which documents curated allelic frequency data pertaining to 144 pharmacogenomics markers across 14 genes, representing approximately 87,000 individuals from 150 populations and ethnic groups worldwide. Long-term sustainability of these resources aims to contribute to the design, development, and implementation of pharmacogenomics testing towards the application of personalized approaches in medical treatment.

Hereditary persistence of fetal hemoglobin (HPFH) is a rare hereditary condition resulting in elevated levels of fetal hemoglobin (HbF) in adults. Typical HPFH is associated with promoter mutations or large deletions affecting the human fetal globin (HBG1 and HBG2) genes, while genetic defects in other genes involved in human erythropoiesis, e.g. KLF1, also result in atypical HPFH. Here, we report the first KLF1 gene promoter mutation (KLF1:g.-148G > A) that is associated with increased HbF level. This mutation was shown to result in drastically reduced CAT reporter gene expression in K562 cells, compared to the wild-type sequence (p = 0.009) and also in reduced KLF1 gene expression in vivo. Furthermore, consistent with in silico analysis, electrophoretic mobility shift analysis showed that the KLF1:g.-148G > A mutation resides in a Sp1 binding site and further that this mutation leads to the ablation of Sp1 binding in vitro. These data suggest that the KLF1:g-148G > A mutation could play a role in increasing HbF levels in adults and further underlines the role of KLF1 as one of the key transcription factors involved in human fetal globin gene switching.

Aims: Bipolar disorder (BD) is a lifelong psychiatric illness characterized by manic and depressive episodes affecting 1–5% of the general population. Among mood-stabilizing treatments, lithium represents the mainstay in the therapeutic management of BD. However, besides the relatively high rate of excellent responders, a significant fraction of patients present patterns of partial or nonresponse to lithium. This variability might be influenced by genetic factors, even though findings have so far been inconclusive. Here, we present the results of an exploratory genome-wide scan followed by extended genotyping carried out on a sample of 204 Sardinian BD patients characterized for lithium response. Materials & methods: Phenotypic assessment of lithium response was made using the retrospective criteria of long-term treatment response scale. Using Affymetrix® 6.0 SNP arrays, we genotyped a subsample of 52 BD patients evenly distributed at the extreme ends of the treatment response scale. The associated SNPs were then prioritized and selected for validation and extended genotyping in the whole sample of BD patients characterized for lithium response. Association was also tested using the scale for a quantitative trait analysis. Results: Our findings showed that several SNPs were nominally associated (p ≤ 10-5) with lithium response in the subgroup of 52 BD subjects. Some association signals were then confirmed in the extended sample. The strongest association, also supported by the quantitative trait analysis, was shown for a SNP located in intron 1 of the ACCN1 gene, encoding for a cation channel with high affinity for sodium and permeable to lithium. Conclusion: Our results indicate that ACCN1 gene is a potential candidate for response to lithium treatment that would serve as a genetic marker of lithium efficacy for BD patients. Original submitted 13 May 2011; Revision submitted 12 July 2011

We report the first heterozygous case of Hb A(2)-NYU (HBD:c.39TA) in the Hellenic population. The proband, an adult female from the island of Crete, Greece, was identified during routine family screening. DEAE chromatography of the index case revealed a minor hemoglobin (Hb) fraction preceding the elution of the wild-type Hb A(2). DNA sequencing of the entire HBD gene coding regions indicated that the index case was heterozygous for the rare variant Hb A(2)-NYU. Family studies indicated that this Hb variant was inherited from the mother. This finding underlines the vast genetic heterogeneity of the HBD gene in the Hellenic population.