Vaginal bacterial load in the second trimester is associated with early preterm birth recurrence: a nested case-control study.

OBJECTIVE: To assess the association between vaginal microbiome (VMB) composition and recurrent early spontaneous preterm birth (sPTB)/preterm prelabour rupture of membranes (PPROM). DESIGN: Nested case-control study. SETTING: UK tertiary referral hospital. SAMPLE: High-risk women with previous sPTB/PPROM <34+0 weeks' gestation who had a recurrence (n = 22) or delivered at ≥37+0 weeks without PPROM (n = 87). METHODS: Vaginal swabs collected between 15 and 22 weeks' gestation were analysed by 16S rRNA gene sequencing and 16S quantitative PCR. MAIN OUTCOME MEASURE: Recurrent early sPTB/PPROM. RESULTS: Of the 109 high-risk women, 28 had anaerobic vaginal dysbiosis, with the remainder dominated by lactobacilli (Lactobacillus iners 36/109, Lactobacillus crispatus 23/109, or other 22/109). VMB type and diversity were not associated with recurrence. Women with a recurrence, compared to those without, had a higher median vaginal bacterial load (8.64 versus 7.89 log10 cells/mcl, adjusted odds ratio [aOR] 1.90, 95% CI 1.01-3.56, P = 0.047) and estimated Lactobacillus concentration (8.59 versus 7.48 log10 cells/mcl, aOR 2.35, (95% CI 1.20-4.61, P = 0.013). A higher recurrence risk was associated with higher median bacterial loads for each VMB type after stratification, although statistical significance was reached only for L. iners domination (aOR 3.44, 95% CI 1.06-11.15, P = 0.040). Women with anaerobic dysbiosis or L. iners domination had a higher median vaginal bacterial load than women with a VMB dominated by L. crispatus or other lactobacilli (8.54, 7.96, 7.63, and 7.53 log10 cells/mcl, respectively). CONCLUSIONS: Vaginal bacterial load is associated with early sPTB/PPROM recurrence. Domination by lactobacilli other than L. iners may protect women from developing high bacterial loads. Future PTB studies should quantify vaginal bacteria and yeasts. TWEETABLE ABSTRACT: Increased vaginal bacterial load in the second trimester may be associated with recurrent early spontaneous preterm birth.

Salivary cortisol response to psychosocial stress in the late evening depends on CRHR1 genotype.

The activation of the hypothalamus-pituitary-adrenal (HPA) axis is induced by stress. Imbalances in this system increase the risk of developing stress related disorders including mental illness. Variants in the single nucleotide polymorphism (SNP) rs110402 of the corticotropin-releasing hormone receptor type I (CRHR1) gene have been shown in interaction with childhood maltreatment to increase the vulnerability to develop depressive symptoms in adulthood. In this study, the direct contribution of polymorphism of the CRHR1 gene (rs110402) to the salivary cortisol response to stress independently from childhood adversity was investigated. Healthy young men between the ages of 18 and 30, free from childhood maltreatment and early trauma, were genotyped (n = 121). To increase the power of the genetic analysis, only homozygous carriers of the common C (n = 31) and of the rare T (n = 21) allele were selected for this study and exposed to a Trier Social Stress Test (TSST) in the late evening (22.30 to 22.40). Salivary samples for the assessment of cortisol and its inactive metabolite cortisone were taken early in the evening (20.00), just before (22.30) and immediately after (22.40) as well as 15 minutes after stress exposure (22.55). Participants with the TT genotype showed higher cortisol levels 15 minutes post stress compared to participants with the CC genotype. No genotype differences were found for cortisone. Interestingly, TT participants reported lower subjective perceived stress levels before the TSST, but not after stress exposure. These results confirm that variants of rs110402 in the CRHR1 gene contribute to an increased stress response. Contrary to previous findings, however, this effect could be observed in subjects reporting no exposure to childhood maltreatment or early trauma.

Should phenotype of previous preterm birth influence management of women with short cervix in subsequent pregnancy? Comparison of vaginal progesterone and Arabin pessary.

OBJECTIVE: To investigate whether the classification of a previous spontaneous preterm birth (sPTB) as preterm labor (PTL) with intact membranes (IM) or as preterm prelabor rupture of membranes (PPROM) impacts the efficacy of cervical pessary or vaginal progesterone for prevention of sPTB in pregnant women with short cervix on transvaginal ultrasound. METHODS: This was a retrospective cohort study of asymptomatic high-risk singleton pregnancies with a short cervix and history of sPTB, treated using Arabin pessary or vaginal progesterone for primary PTB prevention, conducted at four European hospitals. A log-rank test on Kaplan-Meier curves was used to assess the difference in performance of pessary and progesterone, according to history of PTL-IM or PPROM. Linear regression analysis was used to evaluate significant predictors of gestational age at delivery. RESULTS: Between 2008 and 2015, 170 women were treated with a pessary and 88 with vaginal progesterone. In women treated with a pessary, rate of sPTB < 34 weeks was 16% in those with a history of PTL-IM and 55% in those with a history of PPROM. In women treated with progesterone, rate of sPTB < 34 weeks was 13% in those with a history of PTL-IM and 21% in those with a history of PPROM. Treatment with a pessary resulted in earlier delivery in women with previous PPROM than in any other subgroup (P < 0.0001). Linear regression analysis showed a clear effect of PPROM history (P < 0.0001), combination of PPROM history and treatment (P = 0.0003) and cervical length (P = 0.0004) on gestational age at birth. CONCLUSIONS: Cervical pessary may be a less efficacious treatment option for women with previous PPROM; however, these results require prospective validation before change in practice is recommended. Phenotype of previous preterm birth may be an important risk predictor and treatment effect modifier; this information should be reported in future clinical trials. © 2018 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

The protocadherin 17 gene affects cognition, personality, amygdala structure and function, synapse development and risk of major mood disorders.

Major mood disorders, which primarily include bipolar disorder and major depressive disorder, are the leading cause of disability worldwide and pose a major challenge in identifying robust risk genes. Here, we present data from independent large-scale clinical data sets (including 29 557 cases and 32 056 controls) revealing brain expressed protocadherin 17 (PCDH17) as a susceptibility gene for major mood disorders. Single-nucleotide polymorphisms (SNPs) spanning the PCDH17 region are significantly associated with major mood disorders; subjects carrying the risk allele showed impaired cognitive abilities, increased vulnerable personality features, decreased amygdala volume and altered amygdala function as compared with non-carriers. The risk allele predicted higher transcriptional levels of PCDH17 mRNA in postmortem brain samples, which is consistent with increased gene expression in patients with bipolar disorder compared with healthy subjects. Further, overexpression of PCDH17 in primary cortical neurons revealed significantly decreased spine density and abnormal dendritic morphology compared with control groups, which again is consistent with the clinical observations of reduced numbers of dendritic spines in the brains of patients with major mood disorders. Given that synaptic spines are dynamic structures which regulate neuronal plasticity and have crucial roles in myriad brain functions, this study reveals a potential underlying biological mechanism of a novel risk gene for major mood disorders involved in synaptic function and related intermediate phenotypes.

The P2RX7 polymorphism rs2230912 is associated with depression: A meta-analysis.

Various studies have investigated whether single nucleotide polymorphisms (SNPs) in the gene purinergic receptor P2X7 (P2RX7), and rs2230912 specifically, were associated with mood disorders. While some studies found positive evidence, a large number of studies reported no significant associations. In a previously published meta-analysis, Feng et al. did not find a significant association and only moderate odds ratios (ORs) in case-control studies. They reported significant findings only for family-based studies. We revisited this finding and conducted a meta-analysis including 8,652 cases and 11,153 controls, adding unpublished results from the Munich Antidepressant Response Signature (MARS) study. We found a significant association between rs2230912 and combined mood disorders (major depressive disorder (MDD) or bipolar disorder (BD)) for the allelic, dominant and heterozygous-disadvantage model, all withstanding the threshold of correction for multiple testing. Stratifying by disorder revealed significant findings for the MDD-subgroup (OR of 1.12 for the allelic model), while the BD-subgroup presented with a lower effect size (OR of 1.05) and no significance. P2RX7 encodes a purinergic receptor which is expressed in the brain and also localized in immune cells. Animal studies and functional studies will be necessary to enlighten its involvement in the etiology of mood disorders and its applicability for pharmacological purposes.

Genome-wide analysis implicates microRNAs and their target genes in the development of bipolar disorder.

Bipolar disorder (BD) is a severe and highly heritable neuropsychiatric disorder with a lifetime prevalence of 1%. Molecular genetic studies have identified the first BD susceptibility genes. However, the disease pathways remain largely unknown. Accumulating evidence suggests that microRNAs, a class of small noncoding RNAs, contribute to basic mechanisms underlying brain development and plasticity, suggesting their possible involvement in the pathogenesis of several psychiatric disorders, including BD. In the present study, gene-based analyses were performed for all known autosomal microRNAs using the largest genome-wide association data set of BD to date (9747 patients and 14 278 controls). Associated and brain-expressed microRNAs were then investigated in target gene and pathway analyses. Functional analyses of miR-499 and miR-708 were performed in rat hippocampal neurons. Ninety-eight of the six hundred nine investigated microRNAs showed nominally significant P-values, suggesting that BD-associated microRNAs might be enriched within known microRNA loci. After correction for multiple testing, nine microRNAs showed a significant association with BD. The most promising were miR-499, miR-708 and miR-1908. Target gene and pathway analyses revealed 18 significant canonical pathways, including brain development and neuron projection. For miR-499, four Bonferroni-corrected significant target genes were identified, including the genome-wide risk gene for psychiatric disorder CACNB2. First results of functional analyses in rat hippocampal neurons neither revealed nor excluded a major contribution of miR-499 or miR-708 to dendritic spine morphogenesis. The present results suggest that research is warranted to elucidate the precise involvement of microRNAs and their downstream pathways in BD.

Familiality and SNP heritability of age at onset and episodicity in major depressive disorder.

BACKGROUND: Strategies to dissect phenotypic and genetic heterogeneity of major depressive disorder (MDD) have mainly relied on subphenotypes, such as age at onset (AAO) and recurrence/episodicity. Yet, evidence on whether these subphenotypes are familial or heritable is scarce. The aims of this study are to investigate the familiality of AAO and episode frequency in MDD and to assess the proportion of their variance explained by common single nucleotide polymorphisms (SNP heritability). METHOD: For investigating familiality, we used 691 families with 2-5 full siblings with recurrent MDD from the DeNt study. We fitted (square root) AAO and episode count in a linear and a negative binomial mixed model, respectively, with family as random effect and adjusting for sex, age and center. The strength of familiality was assessed with intraclass correlation coefficients (ICC). For estimating SNP heritabilities, we used 3468 unrelated MDD cases from the RADIANT and GSK Munich studies. After similarly adjusting for covariates, derived residuals were used with the GREML method in GCTA (genome-wide complex trait analysis) software. RESULTS: Significant familial clustering was found for both AAO (ICC = 0.28) and episodicity (ICC = 0.07). We calculated from respective ICC estimates the maximal additive heritability of AAO (0.56) and episodicity (0.15). SNP heritability of AAO was 0.17 (p = 0.04); analysis was underpowered for calculating SNP heritability of episodicity. CONCLUSIONS: AAO and episodicity aggregate in families to a moderate and small degree, respectively. AAO is under stronger additive genetic control than episodicity. Larger samples are needed to calculate the SNP heritability of episodicity. The described statistical framework could be useful in future analyses.

Genetic risk prediction and neurobiological understanding of alcoholism.

We have used a translational Convergent Functional Genomics (CFG) approach to discover genes involved in alcoholism, by gene-level integration of genome-wide association study (GWAS) data from a German alcohol dependence cohort with other genetic and gene expression data, from human and animal model studies, similar to our previous work in bipolar disorder and schizophrenia. A panel of all the nominally significant P-value SNPs in the top candidate genes discovered by CFG  (n=135 genes, 713 SNPs) was used to generate a genetic  risk prediction score (GRPS), which showed a trend towards significance (P=0.053) in separating  alcohol dependent individuals from controls in an independent German test cohort. We then validated and prioritized our top findings from this discovery work, and subsequently tested them in three independent cohorts, from two continents. A panel of all the nominally significant P-value single-nucleotide length polymorphisms (SNPs) in the top candidate genes discovered by CFG (n=135 genes, 713 SNPs) were used to generate a Genetic Risk Prediction Score (GRPS), which showed a trend towards significance (P=0.053) in separating alcohol-dependent individuals from controls in an independent German test cohort. In order to validate and prioritize the key genes that drive behavior without some of the pleiotropic environmental confounds present in humans, we used a stress-reactive animal model of alcoholism developed by our group, the D-box binding protein (DBP) knockout mouse, consistent with the surfeit of stress theory of addiction proposed by Koob and colleagues. A much smaller panel (n=11 genes, 66 SNPs) of the top CFG-discovered genes for alcoholism, cross-validated and prioritized by this stress-reactive animal model showed better predictive ability in the independent German test cohort (P=0.041). The top CFG scoring gene for alcoholism from the initial discovery step, synuclein alpha (SNCA) remained the top gene after the stress-reactive animal model cross-validation. We also tested this small panel of genes in two other independent test cohorts from the United States, one with alcohol dependence (P=0.00012) and one with alcohol abuse (a less severe form of alcoholism; P=0.0094). SNCA by itself was able to separate alcoholics from controls in the alcohol-dependent cohort (P=0.000013) and the alcohol abuse cohort (P=0.023). So did eight other genes from the panel of 11 genes taken individually, albeit to a lesser extent and/or less broadly across cohorts. SNCA, GRM3 and MBP survived strict Bonferroni correction for multiple comparisons. Taken together, these results suggest that our stress-reactive DBP animal model helped to validate and prioritize from the CFG-discovered genes some of the key behaviorally relevant genes for alcoholism. These genes fall into a series of biological pathways involved in signal transduction, transmission of nerve impulse (including myelination) and cocaine addiction. Overall, our work provides leads towards a better understanding of illness, diagnostics and therapeutics, including treatment with omega-3 fatty acids. We also examined the overlap between the top candidate genes for alcoholism from this work and the top candidate genes for bipolar disorder, schizophrenia, anxiety from previous CFG analyses conducted by us, as well as cross-tested genetic risk predictions. This revealed the significant genetic overlap with other major psychiatric disorder domains, providing a basis for comorbidity and dual diagnosis, and placing alcohol use in the broader context of modulating the mental landscape.

Discriminating metastasised from non-metastasised seminoma based on transcriptional changes in primary tumours using NGS.

BACKGROUND: We aimed to better discriminate (occult) metastasised from non-metastasised seminoma based on transcriptional changes of small RNAs in the primary tumour. METHODS: Total RNAs including small RNAs were isolated from five testicular tumours of each, lymphogenic, occult and non-metastasised patients. Next-generation sequencing (SOLID, Life Technologies) was used to examine transcriptional changes. Small RNAs showing ⩾50 reads and a significant ⩾2-fold difference using non-metastasised tumours as the reference group were examined in univariate logistic regression analysis and combinations of two small RNAs were further examined using support vector machines. RESULTS: On average, 1.3 × 10(7), 1.4 × 10(7) and 1.7 × 10(7) small RNA reads were detectable in non-metastasised, occult and lymphogenic metastasised seminoma, respectively, of which 30-32% remained after trimming. Between 59 and 68% represented annotated reads and between 8.6 and 11% were annotated small RNA tags. Of them, 137 small RNAs showed>50 reads and a two-fold difference to the reference. In univariate analysis, 32-38 small RNAs significantly discriminated lymphogenic/occult from non-metastasised seminoma, and among these different comparisons, it were the same small RNAs in 51-88%. Many combinations of two of these small RNAs allowed a complete discrimination of metastasised from non-metastasised seminoma irrespective of the metastasis subtype. CONCLUSIONS: Metastasised and non-metastasised seminoma can be completely discriminated with a combination of two small RNAs.

Allelic differences between Europeans and Chinese for CREB1 SNPs and their implications in gene expression regulation, hippocampal structure and function, and bipolar disorder susceptibility.

Bipolar disorder (BD) is a polygenic disorder that shares substantial genetic risk factors with major depressive disorder (MDD). Genetic analyses have reported numerous BD susceptibility genes, while some variants, such as single-nucleotide polymorphisms (SNPs) in CACNA1C have been successfully replicated, many others have not and subsequently their effects on the intermediate phenotypes cannot be verified. Here, we studied the MDD-related gene CREB1 in a set of independent BD sample groups of European ancestry (a total of 64,888 subjects) and identified multiple SNPs significantly associated with BD (the most significant being SNP rs6785[A], P=6.32 × 10(-5), odds ratio (OR)=1.090). Risk SNPs were then subjected to further analyses in healthy Europeans for intermediate phenotypes of BD, including hippocampal volume, hippocampal function and cognitive performance. Our results showed that the risk SNPs were significantly associated with hippocampal volume and hippocampal function, with the risk alleles showing a decreased hippocampal volume and diminished activation of the left hippocampus, adding further evidence for their involvement in BD susceptibility. We also found the risk SNPs were strongly associated with CREB1 expression in lymphoblastoid cells (P<0.005) and the prefrontal cortex (P<1.0 × 10(-6)). Remarkably, population genetic analysis indicated that CREB1 displayed striking differences in allele frequencies between continental populations, and the risk alleles were completely absent in East Asian populations. We demonstrated that the regional prevalence of the CREB1 risk alleles in Europeans is likely caused by genetic hitchhiking due to natural selection acting on a nearby gene. Our results suggest that differential population histories due to natural selection on regional populations may lead to genetic heterogeneity of susceptibility to complex diseases, such as BD, and explain inconsistencies in detecting the genetic markers of these diseases among different ethnic populations.

A common variant in myosin-18B contributes to mathematical abilities in children with dyslexia and intraparietal sulcus variability in adults.

The ability to perform mathematical tasks is required in everyday life. Although heritability estimates suggest a genetic contribution, no previous study has conclusively identified a genetic risk variant for mathematical performance. Research has shown that the prevalence of mathematical disabilities is increased in children with dyslexia. We therefore correlated genome-wide data of 200 German children with spelling disability, with available quantitative data on mathematic ability. Replication of the top findings in additional dyslexia samples revealed that rs133885 was a genome-wide significant marker for mathematical abilities (P(comb) = 7.71 × 10(-10), n = 699), with an effect size of 4.87%. This association was also found in a sample from the general population (P = 0.048, n = 1080), albeit with a lower effect size. The identified variant encodes an amino-acid substitution in MYO18B, a protein with as yet unknown functions in the brain. As areas of the parietal cortex, in particular the intraparietal sulcus (IPS), are involved in numerical processing in humans, we investigated whether rs133885 was associated with IPS morphology using structural magnetic resonance imaging data from 79 neuropsychiatrically healthy adults. Carriers of the MYO18B risk-genotype displayed a significantly lower depth of the right IPS. This validates the identified association between rs133885 and mathematical disability at the level of a specific intermediate phenotype.

Variants within the GABA transaminase (ABAT) gene region are associated with somatosensory evoked EEG potentials in families at high risk for affective disorders.

BACKGROUND: Depression frequently co-occurs with somatization, and somatic complaints have been reported as a vulnerability marker for affective disorders observable before disease onset. Somatization is thought to result from an increased attention to somatic sensations, which should be reflected in long-latency somatosensory evoked electroencephalogram (EEG) potentials (SSEPs) at the physiological level. Previous studies revealed that SSEPs are altered in depressed patients and suggested late SSEP components as vulnerability markers for affective disorders. Neurotransmitters such as serotonin, γ-aminobutyric acid (GABA) and the neuropeptide substance P may play an important role for both affective disorders and somatosensory processing. Method We investigated the associations between SSEPs and polymorphisms within candidate genes of the serotonergic, GABAergic as well as the substance P system in subjects at high risk for affective disorders. The sample was composed of high-risk families participating in the Munich Vulnerability Study and genetic association analyses were calculated using qfam (family-based association tests for quantitative traits) implemented in PLINK 1.05. RESULTS: We observed significant associations (false discovery rate <0.05) withstanding correction for multiple testing between late SSEP components (response strength 170-370 ms after stimulation) and four single nucleotide polymorphisms within the GABA transaminase (ABAT) gene region coding for a protein responsible for GABA degradation. No effects were found with the classical disease trait approach, suggesting SSEP marker specificity of the observed associations. CONCLUSIONS: Our findings point to a possible role of ABAT gene-regulated GABA catabolism for an altered processing of somatosensory stimuli as a potential vulnerability marker for affective disorders.

A K(ATP) channel gene effect on sleep duration: from genome-wide association studies to function in Drosophila.

Humans sleep approximately a third of their lifetime. The observation that individuals with either long or short sleep duration show associations with metabolic syndrome and psychiatric disorders suggests that the length of sleep is adaptive. Although sleep duration can be influenced by photoperiod (season) and phase of entrainment (chronotype), human familial sleep disorders indicate that there is a strong genetic modulation of sleep. Therefore, we conducted high-density genome-wide association studies for sleep duration in seven European populations (N=4251). We identified an intronic variant (rs11046205; P=3.99 × 10(-8)) in the ABCC9 gene that explains ≈5% of the variation in sleep duration. An influence of season and chronotype on sleep duration was solely observed in the replication sample (N=5949). Meta-analysis of the associations found in a subgroup of the replication sample, chosen for season of entry and chronotype, together with the discovery results showed genome-wide significance. RNA interference knockdown experiments of the conserved ABCC9 homologue in Drosophila neurons renders flies sleepless during the first 3 h of the night. ABCC9 encodes an ATP-sensitive potassium channel subunit (SUR2), serving as a sensor of intracellular energy metabolism.

Estimating the heritability of reporting stressful life events captured by common genetic variants.

BACKGROUND: Although usually thought of as external environmental stressors, a significant heritable component has been reported for measures of stressful life events (SLEs) in twin studies. Method We examined the variance in SLEs captured by common genetic variants from a genome-wide association study (GWAS) of 2578 individuals. Genome-wide complex trait analysis (GCTA) was used to estimate the phenotypic variance tagged by single nucleotide polymorphisms (SNPs). We also performed a GWAS on the number of SLEs, and looked at correlations between siblings. RESULTS: A significant proportion of variance in SLEs was captured by SNPs (30%, p = 0.04). When events were divided into those considered to be dependent or independent, an equal amount of variance was explained for both. This 'heritability' was in part confounded by personality measures of neuroticism and psychoticism. A GWAS for the total number of SLEs revealed one SNP that reached genome-wide significance (p = 4 × 10-8), although this association was not replicated in separate samples. Using available sibling data for 744 individuals, we also found a significant positive correlation of R 2 = 0.08 in SLEs (p = 0.03). CONCLUSIONS: These results provide independent validation from molecular data for the heritability of reporting environmental measures, and show that this heritability is in part due to both common variants and the confounding effect of personality.

Cost-effective GPU-grid for genome-wide epistasis calculations.

BACKGROUND: Until recently, genotype studies were limited to the investigation of single SNP effects due to the computational burden incurred when studying pairwise interactions of SNPs. However, some genetic effects as simple as coloring (in plants and animals) cannot be ascribed to a single locus but only understood when epistasis is taken into account [1]. It is expected that such effects are also found in complex diseases where many genes contribute to the clinical outcome of affected individuals. Only recently have such problems become feasible computationally. OBJECTIVES: The inherently parallel structure of the problem makes it a perfect candidate for massive parallelization on either grid or cloud architectures. Since we are also dealing with confidential patient data, we were not able to consider a cloud-based solution but had to find a way to process the data in-house and aimed to build a local GPU-based grid structure. METHODS: Sequential epistatsis calculations were ported to GPU using CUDA at various levels. Parallelization on the CPU was compared to corresponding GPU counterparts with regards to performance and cost. RESULTS: A cost-effective solution was created by combining custom-built nodes equipped with relatively inexpensive consumer-level graphics cards with highly parallel GPUs in a local grid. The GPU method outperforms current cluster-based systems on a price/performance criterion, as a single GPU shows speed performance comparable up to 200 CPU cores. CONCLUSION: The outlined approach will work for problems that easily lend themselves to massive parallelization. Code for various tasks has been made available and ongoing development of tools will further ease the transition from sequential to parallel algorithms.

Replication and meta-analysis of TMEM132D gene variants in panic disorder.

A recent genome-wide association study in patients with panic disorder (PD) identified a risk haplotype consisting of two single-nucleotide polymorphisms (SNPs) (rs7309727 and rs11060369) located in intron 3 of TMEM132D to be associated with PD in three independent samples. Now we report a subsequent confirmation study using five additional PD case-control samples (n = 1670 cases and n = 2266 controls) assembled as part of the Panic Disorder International Consortium (PanIC) study for a total of 2678 cases and 3262 controls in the analysis. In the new independent samples of European ancestry (EA), the association of rs7309727 and the risk haplotype rs7309727-rs11060369 was, indeed, replicated, with the strongest signal coming from patients with primary PD, that is, patients without major psychiatric comorbidities (n = 1038 cases and n = 2411 controls). This finding was paralleled by the results of the meta-analysis across all samples, in which the risk haplotype and rs7309727 reached P-levels of P = 1.4e-8 and P = 1.1e-8, respectively, when restricting the samples to individuals of EA with primary PD. In the Japanese sample no associations with PD could be found. The present results support the initial finding that TMEM132D gene contributes to genetic susceptibility for PD in individuals of EA. Our results also indicate that patient ascertainment and genetic background could be important sources of heterogeneity modifying this association signal in different populations.

Genome-wide significant association between a 'negative mood delusions' dimension in bipolar disorder and genetic variation on chromosome 3q26.1.

Research suggests that clinical symptom dimensions may be more useful in delineating the genetics of bipolar disorder (BD) than standard diagnostic models. To date, no study has applied this concept to data from genome-wide association studies (GWAS). We performed a GWAS of factor dimensions in 927 clinically well-characterized BD patients of German ancestry. Rs9875793, which is located in an intergenic region of 3q26.1 and in the vicinity of the solute carrier family 2 (facilitated glucose transporter), member 2 gene (SLC2A2), was significantly associated with the factor analysis-derived dimension 'negative mood delusions' (n=927; P=4.65 × 10(-8), odds ratio (OR)=2.66). This dimension was comprised of the symptoms delusions of poverty, delusions of guilt and nihilistic delusions. In case-control analyses, significant association with the G allele of rs9875793 was only observed in the subgroup of BD patients who displayed symptoms of 'negative mood delusions' (allelic χ(2) model: P(G)=0.0001, OR=1.92; item present, n=89). Further support for the hypothesis that rs9875793 is associated with BD in patients displaying 'negative mood delusions' symptom, such as delusions of guilt, was obtained from an European American sample (GAIN/TGEN), which included 1247 BD patients and 1434 controls (P(EA)=0.028, OR=1.27).

Evidence for the involvement of ZNF804A in cognitive processes of relevance to reading and spelling.

Previous studies have shown that individuals with schizophrenia and dyslexia display common neurocognitive abnormalities. The aim of the present study was to determine whether known schizophrenia-risk genes contribute to dyslexia risk or to disease-relevant cognitive functions. For this purpose, we genotyped the schizophrenia-associated risk variants within zinc-finger protein 804A (ZNF804A), transcription-factor 4 and neurogranin in a large dyslexia case-control sample. We tested all variants for association with dyslexia (927 cases, 1096 controls), and with eight language-relevant cognitive processes (1552 individuals). We observed six significant associations between language-relevant traits and the ZNF804A-variant rs1344706. Interestingly, the ZNF804A schizophrenia risk variant was associated with a better cognitive performance in our data set. This finding might be consistent with a previously reported ZNF804A association in schizophrenia, in which patients carrying the schizophrenia-risk allele at rs1344706 showed a better performance in two memory tests. In conclusion, the present study provides evidence that ZNF804A might have a role in cognitive traits of relevance to reading and spelling, and underlines the phenotypic complexity that might be associated with ZNF804A.

Restless legs syndrome in Czech patients with multiple sclerosis: an epidemiological and genetic study.

BACKGROUND: Restless legs syndrome (RLS) is a frequent neurological disorder which is presented in idiopathic and secondary form. Idiopathic RLS is associated with common genetic variants in four chromosomal regions. Recently, multiple sclerosis (MS) was identified as a common cause for secondary RLS. The aim of our study was to evaluate the prevalence of RLS among Czech patients with MS and to further analyze the impact of known genetic risk factors for RLS in patients with MS. METHODS: Each patient underwent a semi-structured interview. A patient was considered to be affected by RLS if all four standard criteria had ever been met in their lifetime. The sample was genotyped using 12 single nucleotide polymorphisms within the four genomic regions, which were selected according to the results of previous genome-wide association studies. RESULTS: A total of 765 subjects with MS were included in the study and the diagnosis of RLS was confirmed in 245 subjects (32.1%, 95%CI 28.7-35.4%). The genetic association study included 642 subjects; 203 MS patients with RLS were compared to 438 MS patients without RLS. No significant association with MEIS 1, BTBD9, and PTPRD gene variants was found despite sufficient statistical power for the first two loci. There was a trend for association with the MAP2K5/SCOR1 gene - the best model for the risk allele was the recessive one (p nominal=0.0029, p corrected for four loci and two models=0.023, odds ratio=1.60). CONCLUSION: We confirmed that RLS prevalence was high in patients with multiple sclerosis, but this form did not share all genetic risk variants with idiopathic RLS.

Single-nucleotide polymorphisms in HLA- and non-HLA genes associated with the development of antibodies to interferon-ß therapy in multiple sclerosis patients.

Interferons-ß (IFN-ß) are the most widely used immunomodulatory drugs for treatment of multiple sclerosis (MS). The development of neutralizing antibodies (NABs) against IFN-ß is one of the main reasons for treatment failure. While formulation of the drug has a proven impact on the development of NABs, the genetic predisposition to develop antibodies is poorly understood. We performed genome-wide single-nucleotide polymorphism (SNP) genotyping in 362 MS patients of whom 178 had developed and 184 had not developed antibodies on IFN-ß therapy. Four candidate SNPs were validated in an independent cohort of 350 antibody-positive and 468 antibody-negative MS patients. One SNP within the human leucocyte antigen (HLA) region (rs9272105, P-value: 3.56 × 10⁻¹°) and one SNP in an intergenic region on chromosome 8q24.3 (rs4961252, P-value: 2.92 × 10⁻8 showed a genome-wide significant association with the anti-IFN-ß antibody titers. We found no interaction between the genome-wide significant SNPs (rs9272105 and rs4961252) in our study and the previously described HLA-DR*0401 or *0408 alleles, indicating an additive effect of SNPs and HLA alleles. Testing for these SNPs and the HLA-DR*0401 or *0408 alleles allows to identify patients at risk to develop antibodies to IFN-ß and may provide helpful information for individual treatment decisions.