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Contains fulltext : 177554.pdf (Publisher’s version ) (Closed access) Nonsyndromic cleft palate only (nsCPO) is a facial malformation that has a livebirth prevalence of 1 in 2,500. Research suggests that the etiology of nsCPO is multifactorial, with a clear genetic component. To date, genome-wide association studies have identified only 1 conclusive common variant for nsCPO, that is, a missense variant in the gene grainyhead-like-3 ( GRHL3). Thus, the underlying genetic causes of nsCPO remain largely unknown. The present study aimed at identifying rare variants that might contribute to nsCPO risk, via whole-exome sequencing (WES), in multiply affected Central European nsCPO pedigrees. WES was performed in 2 affected first-degree relatives from each family. Variants shared between both individuals were analyzed for their potential deleterious nature and a low frequency in the general population. Genes carrying promising variants were annotated for 1) reported associations with facial development, 2) multiple occurrence of variants, and 3) expression in mouse embryonic palatal shelves. This strategy resulted in the identification of a set of 26 candidate genes that were resequenced in 132 independent nsCPO cases and 623 independent controls of 2 different ethnicities, using molecular inversion probes. No rare loss-of-function mutation was identified in either WES or resequencing step. However, we identified 2 or more missense variants predicted to be deleterious in each of 3 genes ( ACACB, PTPRS, MIB1) in individuals from independent families. In addition, the analyses identified a novel variant in GRHL3 in 1 patient and a variant in CREBBP in 2 siblings. Both genes underlie different syndromic forms of CPO. A plausible hypothesis is that the apparently nonsyndromic clefts in these 3 patients might represent hypomorphic forms of the respective syndromes. In summary, the present study identified rare variants that might contribute to nsCPO risk and suggests candidate genes for further investigation.

Background The genes Gremlin-1 (GREM1) and Noggin (NOG) are components of the bone morphogenetic protein 4 pathway, which has been implicated in craniofacial development. Both genes map to recently identified susceptibility loci (chromosomal region 15q13, 17q22) for nonsyndromic cleft lip with or without cleft palate (nsCL/P). The aim of the present study was to determine whether rare variants in either gene are implicated in nsCL/P etiology. Methods The complete coding regions, untranslated regions, and splice sites of GREM1 and NOG were sequenced in 96 nsCL/P patients and 96 controls of Central European ethnicity. Three burden and four nonburden tests were performed. Statistically significant results were followed up in a second case-control sample (n = 96, respectively). For rare variants observed in cases, segregation analyses were performed. Results In NOG, four rare sequence variants (minor allele frequency

Summary Background Male-pattern baldness (androgenetic alopecia, AGA) is the most common form of hair loss among humans. Research has shown that it is caused by genetic factors. Numerous studies have unequivocally identified two major genetic risk loci for AGA: the X-chromosomal AR/EDA2R locus, and the PAX1/FOXA2 locus on chromosome 20. Objectives To identify further candidate genes for AGA, and thus gain further insights into this phenotype. Methods A German sample of 581 severely affected cases and 617 controls was used to perform a genome-wide association study. The identified associated locus was further analysed by fine-mapping, and then independently replicated in an Australian sample. Expression and pathway analyses were performed to characterize the susceptibility gene identified. Results The most significant association signal was obtained for rs756853 (P = 1·64 × 10−7), which is located intronically in the histone deacetylase 9 (HDAC9) gene. Fine-mapping and a family-based analysis revealed that rs756853 and the 6-kb distal rs2249817 were the most highly associated single nucleotide polymorphisms. The association finding was replicated in an independent Australian sample, when the analysis was restricted to severely affected cases and unaffected controls (P = 0·026). Analysis of rs2249817 in a combined sample of severely affected German and Australian cases and unaffected controls revealed a strong association signal (P = 9·09 × 10−8). Tissue expression studies demonstrated HDAC9 expression in various tissues, including tissues of relevance to AGA. No strong genotypic effects were observed in genotype-specific expression or splice studies. Pathway analyses supported the hypothesis that HDAC9 plays a functional role in AGA via interaction with the AR gene. Conclusions The present study suggests that HDAC9 is the third AGA susceptibility gene.

Alopecia areata (AA) is a common hair loss disorder, which is thought to be a tissue-specific autoimmune disease. Previous research has identified a few AA susceptibility genes, most of which are implicated in autoimmunity. To identify new genetic variants and further elucidate the genetic basis of AA, we performed a genome-wide association study using the strategy of pooled DNA genotyping (729 cases, 656 controls). The strongest association was for variants in the HLA region, which confirms the validity of the pooling strategy. The selected top 61 single-nucleotide polymorphisms (SNPs) were analyzed in an independent replication sample (454 cases, 1364 controls). Only one SNP outside of the HLA region (rs304650) showed significant association. This SNP was then analyzed in a second independent replication sample (537 cases, 657 controls). The finding was not replicated on a significant level, but showed the same tendency. A combined analysis of the two replication samples was then performed, and the SNP rs304650 showed significant association with P=3.43 x 10(-4) (OR=1.24 (1.10-1.39)). This SNP maps to an intronic region of the SPATA5 (spermatogenesis-associated protein 5) gene on chromosome 4. The results therefore suggest the SPATA5 locus is a new susceptibility locus for AA. European Journal of Human Genetics (2012) 20, 326-332; doi:10.1038/ejhg.2011.185; published online 26 October 2011

Nonsyndromic orofacial clefting (nsOFC) is a common, complex congenital disorder. The most frequent forms are nonsyndromic cleft lip with or without cleft palate (nsCL/P) and nonsyndromic cleft palate only (nsCPO). Although they are generally considered distinct entities, a recent study has implicated a region around the FOXE1 gene in both nsCL/P and nsCPO. To investigate this hypothesis, we analyzed the 2 most strongly associated markers (rs3758249 and rs4460498) in 2 independent samples of differing ethnicities: Central European (949 nsCL/P cases, 155 nsCPO cases, 1163 controls) and Mayan Mesoamerican (156 nsCL/P cases, 10 nsCPO cases, 338 controls). While highly significant associations for both single-nucleotide polymorphisms were obtained in nsCL/P (rs4460498: pEurope = 6.50 × 10−06, pMayan = .0151; rs3758249: pEurope = 2.41 × 10−05, pMayan = .0299), no association was found in nsCPO ( p > .05). Genotyping of rs4460498 in 472 independent European trios revealed significant associations for nsCL/P ( p = .016) and nsCPO ( p = .043). A meta-analysis of all data revealed a genomewide significant result for nsCL/P ( p = 1.31 × 10−08), which became more significant when nsCPO cases were added ( pnsOFC = 1.56 × 10−09). These results strongly support the FOXE1 locus as a risk factor for nsOFC. With the data of the initial study, there is now considerable evidence that this locus is the first conclusive risk factor shared between nsCL/P and nsCPO.

We carried out a genome-wide association study in 296 individuals with male-pattern baldness (androgenetic alopecia) and 347 controls. We then investigated the 30 best SNPs in an independent replication sample and found highly significant association for five SNPs on chromosome 20p11 (rs2180439 combined P = 2.7 x 10(-15)). No interaction was detected with the X-chromosomal androgen receptor locus, suggesting that the 20p11 locus has a role in a yet-to-be-identified androgen-independent pathway.

We have conducted the first meta-analyses for nonsyndromic cleft lip with or without cleft palate (NSCL/P) using data from the two largest genome-wide association studies published to date. We confirmed associations with all previously identified loci and identified six additional susceptibility regions (1p36, 2p21, 3p11.1, 8q21.3, 13q31.1 and 15q22). Analysis of phenotypic variability identified the first specific genetic risk factor for NSCLP (nonsyndromic cleft lip plus palate) (rs8001641; P-NSCLP = 6.51 x 10(-11); homozygote relative risk = 2.41, 95% confidence interval (CI) 1.84-3.16).

Convergent evidence from pharmacological and animal studies suggests a possible role for the synaptic vesicle glycoprotein 2A gene (SV2A) in schizophrenia susceptibility. To test systematically all common variants in the SV2A gene region for an association with schizophrenia, we used a HapMap-based haplotype tagging approach and tested five SNPs in 794 patients and 843 controls. The SNP rs15931 showed evidence for an association with schizophrenia and was followed-up in an independent sample of 2581 individuals (overall p-value = 0.0042, OR = 0.779). Our study in the German population provides evidence, at a genetic level, for the involvement of the SV2A gene region in schizophrenia.

We used genome-wide single nucleotide polymorphism (SNP) data to search for the presence of copy number variants (CNVs) in 882 patients with bipolar disorder (BD) and 872 population-based controls. A total of 291 (33%) patients had an early age-at-onsetor =21 years (AOor =21 years). We systematically filtered for CNVs that cover at least 30 consecutive SNPs and which directly affect at least one RefSeq gene. We tested whether (a) the genome-wide burden of these filtered CNVs differed between patients and controls and whether (b) the frequency of specific CNVs differed between patients and controls. Genome-wide burden analyses revealed that the frequency and size of CNVs did not differ substantially between the total samples of BD patients and controls. However, separate analysis of patients with AOor =21 years and AO21 years showed that the frequency of microduplications was significantly higher (P=0.0004) and the average size of singleton microdeletions was significantly larger (P=0.0056) in patients with AOor =21 years compared with controls. A search for specific BD-associated CNVs identified two common CNVs: (a) a 160 kb microduplication on 10q11 was overrepresented in AOor = 21 years patients (9.62%) compared with controls (3.67%, P=0.0005) and (b) a 248 kb microduplication on 6q27 was overrepresented in the AOor = 21 years subgroup (5.84%) compared with controls (2.52%, P=0.0039). These data suggest that CNVs have an influence on the development of early-onset, but not later-onset BD. Our study provides further support for previous hypotheses of an etiological difference between early-onset and later-onset BD.

Strong evidence of linkage between chromosomal region 6q16-q22 and bipolar affective disorder (BPAD) has previously been reported. We conducted a systematic association mapping of the 6q-linkage interval using 617 SNP markers in a BPAD case–control sample of German descent (cases = 330, controls = 325). In this screening step, 46 SNPs showed nominally significant BPAD-association (P-values between 0.0007 and 0.0484). Although none of the 46 SNPs survived correction for multiple testing, they were genotyped in a second and ethnically matched BPAD sample (cases = 328, controls = 397). At the melanin-concentrating-hormone-receptor-2 (MCHR2) gene, we found nominal association in both the initial and second BPAD samples (combined P = 0.008). This finding was followed up by the genotyping of 17 additional MCHR2-SNPs in the combined sample in order to define our findings more precisely. We found that the MCHR2-locus can be divided into three different haplotype-blocks, and observed that the MCHR2-association was most pronounced in BPAD male patients with psychotic symptoms. In two neighboring blocks, putative risk-haplotypes were found to be 7% more frequent in patients (block II: 23.3% vs. 16.2%, P = 0.005, block III: 39.2% vs. 32.0%, P = 0.024), whereas the putative protective haplotypes were found to be 5–8% less frequent in patients (block II: 11.6% vs. 16.4%, P = 0.041, block III: 30.0% vs. 38.8%, P = 0.007). The corresponding odds ratios (single-marker analysis) ranged between 1.25 and 1.46. Our findings may indicate that MCHR2 is a putative risk factor for BPAD. These findings should be interpreted with caution and replicated in independent BPAD samples.

Contains fulltext : 80032.pdf (Publisher’s version ) (Closed access) We conducted a genome-wide association study involving 224 cases and 383 controls of Central European origin to identify susceptibility loci for nonsyndromic cleft lip with or without cleft palate (NSCL/P). A 640-kb region at chromosome 8q24.21 was found to contain multiple markers with highly significant evidence for association with the cleft phenotype, including three markers that reached genome-wide significance. The 640-kb cleft-associated region was saturated with 146 SNP markers and then analyzed in our entire NSCL/P sample of 462 unrelated cases and 954 controls. In the entire sample, the most significant SNP (rs987525) had a P value of 3.34 x 10(-24). The odds ratio was 2.57 (95% CI = 2.02-3.26) for the heterozygous genotype and 6.05 (95% CI = 3.88-9.43) for the homozygous genotype. The calculated population attributable risk for this marker is 0.41, suggesting that this study has identified a major susceptibility locus for NSCL/P.