Anorexia nervosa (AN) is a complex psychiatric disorder with both psychiatric and metabolic underpinnings. This study aims to explore the genetic architecture of AN and the interplay between its psych Show more
Anorexia nervosa (AN) is a complex psychiatric disorder with both psychiatric and metabolic underpinnings. This study aims to explore the genetic architecture of AN and the interplay between its psychiatric and metabolic components. Through a meta-analysis of AN GWAS data from European and Finnish populations, we identified a novel genome-wide significant locus near the SOX5 gene. Genetic correlation and Mendelian randomization analyses revealed shared and potentially causal relationships between AN and multiple psychiatric and metabolic traits. Local genetic correlation analysis identified 185 significant genomic regions contributing to shared heritability between AN and correlated phenotypes, with 100 loci demonstrating pleiotropic effects across multiple traits. The MTAG analyses identified 86 significant loci (34 overlapping with local genetic correlation results), including 25 novel loci such as brain-relevant VAMP2 (17p13.1) and metabolic-neurological hubs LPL (8p21.3) and BDNF (11p14.1). Gene Co-expression Network Analysis (WGCNA) further identified key gene modules associated with both metabolic and neurological pathways, particularly highlighting synaptic signaling and lipid metabolism. Single-cell transcriptomic analysis further resolved this genetic risk to the cellular level, confirming its concentration in limbic and striatal GABAergic neurons and extending the implicated circuitry to include cortical regions involved in motor function. These findings collectively demonstrate the intricate genetic interplay between psychiatric and metabolic pathways in AN, underscoring the necessity of an integrated approach to understanding its pathogenesis. Show less
Diabetes impacts approximately 200 million people worldwide, of whom approximately 10% are affected by type 1 diabetes (T1D). The application of genome-wide association studies (GWAS) has robustly rev Show more
Diabetes impacts approximately 200 million people worldwide, of whom approximately 10% are affected by type 1 diabetes (T1D). The application of genome-wide association studies (GWAS) has robustly revealed dozens of genetic contributors to the pathogenesis of T1D, with the most recent meta-analysis identifying in excess of 40 loci. To identify additional genetic loci for T1D susceptibility, we examined associations in the largest meta-analysis to date between the disease and ā¼2.54 million SNPs in a combined cohort of 9,934 cases and 16,956 controls. Targeted follow-up of 53 SNPs in 1,120 affected trios uncovered three new loci associated with T1D that reached genome-wide significance. The most significantly associated SNP (rs539514, Pā=ā5.66Ć10ā»Ā¹Ā¹) resides in an intronic region of the LMO7 (LIM domain only 7) gene on 13q22. The second most significantly associated SNP (rs478222, Pā=ā3.50Ć10ā»ā¹ resides in an intronic region of the EFR3B (protein EFR3 homolog B) gene on 2p23; however, the region of linkage disequilibrium is approximately 800 kb and harbors additional multiple genes, including NCOA1, C2orf79, CENPO, ADCY3, DNAJC27, POMC, and DNMT3A. The third most significantly associated SNP (rs924043, Pā=ā8.06Ć10ā»ā¹ lies in an intergenic region on 6q27, where the region of association is approximately 900 kb and harbors multiple genes including WDR27, C6orf120, PHF10, TCTE3, C6orf208, LOC154449, DLL1, FAM120B, PSMB1, TBP, and PCD2. These latest associated regions add to the growing repertoire of gene networks predisposing to T1D. Show less
Neuroblastoma is a malignant neoplasm of the developing sympathetic nervous system that is notable for its phenotypic diversity. High-risk patients typically have widely disseminated disease at diagno Show more
Neuroblastoma is a malignant neoplasm of the developing sympathetic nervous system that is notable for its phenotypic diversity. High-risk patients typically have widely disseminated disease at diagnosis and a poor survival probability, but low-risk patients frequently have localized tumors that are almost always cured with little or no chemotherapy. Our genome-wide association study (GWAS) has identified common variants within FLJ22536, BARD1, and LMO1 as significantly associated with neuroblastoma and more robustly associated with high-risk disease. Here we show that a GWAS focused on low-risk cases identified SNPs within DUSP12 at 1q23.3 (P = 2.07 Ć 10ā»ā¶), DDX4 and IL31RA both at 5q11.2 (P = 2.94 Ć 10ā»ā¶ and 6.54 Ć 10ā»ā· respectively), and HSD17B12 at 11p11.2 (P = 4.20 Ć 10ā»ā·) as being associated with the less aggressive form of the disease. These data demonstrate the importance of robust phenotypic data in GWAS analyses and identify additional susceptibility variants for neuroblastoma. Show less
Obesity is a serious health concern for children and adolescents, particularly in Western societies, where its incidence is now considered to have reached epidemic proportions. A number of genetic det Show more
Obesity is a serious health concern for children and adolescents, particularly in Western societies, where its incidence is now considered to have reached epidemic proportions. A number of genetic determinants of adult BMI have already been established through genome wide association studies (GWAS), most recently from the GIANT meta-analysis of such datasets combined. In this current study of European Americans, we examined the 32 loci detected in that GIANT study in the context of common childhood obesity within a cohort of 1,097 cases (defined as BMI ā„95th percentile), together with 2,760 lean controls (defined as BMI <50th percentile), aged between 2 and 18 years old. Nine of these single-nucleotide polymorphims (SNPs) yielded at least nominal evidence for association with common childhood obesity, namely at the FTO, TMEM18, NRXN3, MC4R, SEC16B, GNPDA2, TNNI3K, QPCTL, and BDNF loci. However, overall 28 of the 32 loci showed directionally consistent effects to that of the adult BMI meta-analysis. We conclude that among the 32 loci that have been reported to associate with adult BMI in the largest meta-analysis of BMI to date, at least nine also contribute to the determination of common obesity in childhood in European Americans, as demonstrated by their associations in our pediatric cohort. Show less
Large-scale genome-wide association studies (GWAS) have identified many loci associated with body mass index (BMI), but few studies focused on obesity as a binary trait. Here we report the results of Show more
Large-scale genome-wide association studies (GWAS) have identified many loci associated with body mass index (BMI), but few studies focused on obesity as a binary trait. Here we report the results of a GWAS and candidate SNP genotyping study of obesity, including extremely obese cases and never overweight controls as well as families segregating extreme obesity and thinness. We first performed a GWAS on 520 cases (BMI>35 kg/m(2)) and 540 control subjects (BMI<25 kg/m(2)), on measures of obesity and obesity-related traits. We subsequently followed up obesity-associated signals by genotyping the top ā¼500 SNPs from GWAS in the combined sample of cases, controls and family members totaling 2,256 individuals. For the binary trait of obesity, we found 16 genome-wide significant signals within the FTO gene (strongest signal at rs17817449, P = 2.5 Ć 10(-12)). We next examined obesity-related quantitative traits (such as total body weight, waist circumference and waist to hip ratio), and detected genome-wide significant signals between waist to hip ratio and NRXN3 (rs11624704, P = 2.67 Ć 10(-9)), previously associated with body weight and fat distribution. Our study demonstrated how a relatively small sample ascertained through extreme phenotypes can detect genuine associations in a GWAS. Show less
Interindividual variation in response to anti-TNFalpha therapy may be explained by genetic variability in disease pathogenesis or mechanism of action. Recent genome-wide association studies (GWAS) in Show more
Interindividual variation in response to anti-TNFalpha therapy may be explained by genetic variability in disease pathogenesis or mechanism of action. Recent genome-wide association studies (GWAS) in inflammatory bowel disease (IBD) have increased our understanding of the genetic susceptibility to IBD. The aim was to test associations of known IBD susceptibility loci and novel "pharmacogenetic" GWAS identified loci with primary nonresponse to anti-TNFalpha in pediatric IBD patients and develop a predictive model of primary nonresponse. Primary nonresponse was defined using the Harvey Bradshaw Index (HBI) for Crohn's disease (CD) and partial Mayo score for ulcerative colitis (UC). Genotyping was performed using the Illumina Infinium platform. Chi-square analysis tested associations of phenotype and genotype with primary nonresponse. Genetic associations were identified by testing known IBD susceptibility loci and by performing a GWAS for primary nonresponse. Stepwise multiple logistic regression was performed to build predictive models. Nonresponse occurred in 22 of 94 subjects. Six known susceptibility loci were associated with primary nonresponse (P < 0.05). Only the 21q22.2/BRWDI loci remained significant in the predictive model. The most predictive model included 3 novel "pharmacogenetic" GWAS loci, the previously identified BRWD1, pANCA, and a UC diagnosis (R(2) = 0.82 and area under the curve [AUC] = 0.98%). The relative risk of nonresponse increased 15-fold when number of risk factors increased from 0-2 to > or =3. The combination of phenotype and genotype is most predictive of primary nonresponse to anti-TNFalpha in pediatric IBD. Defining predictors of response to anti-TNFalpha may allow the identification of patients who will not benefit from this class of therapy. Show less