Two-stage Genome-wide Methylation Profiling in Childhood-onset Crohn's Disease Implicates Epigenetic Alterations at the VMP1/MIR21 and HLA Loci

Background: As a result of technological and analytical advances, genome-wide characterization of key epigenetic alterations is now feasible in complex diseases. We hypothesized that this may provide important insights into gene-environmental interactions in Crohn's disease (CD) and is especially pertinent to early onset disease. Methods: The Illumina 450K platform was applied to assess epigenome-wide methylation profiles in circulating leukocyte DNA in discovery and replication pediatric CD cohorts and controls. Data were corrected for differential leukocyte proportions. Targeted replication was performed in adults using pyrosequencing. Methylation changes were correlated with gene expression in blood and intestinal mucosa. Results: We identified 65 individual CpG sites with methylation alterations achieving epigenome-wide significance after Bonferroni correction (P &#60; 1.1 × 10−7), and 19 differently methylated regions displaying unidirectional methylation change. There was a highly significant enrichment of methylation changes around GWAS single nucleotide polymorphisms (P = 3.7 × 10−7), notably the HLA region and MIR21. Two-locus discriminant analysis in the discovery cohort predicted disease in the pediatric replication cohort with high accuracy (area under the curve, 0.98). The findings strongly implicate the transcriptional start site of MIR21 as a region of extended epigenetic alteration, containing the most significant individual probes (P = 1.97 × 10−15) within a GWAS risk locus. In extension studies, we confirmed hypomethylation of MIR21 in adults (P = 6.6 × 10−5, n = 172) and show increased mRNA expression in leukocytes (P &#60; 0.005, n = 66) and in the inflamed intestine (P = 1.4 × 10−6, n = 99). Conclusions: We demonstrate highly significant and replicable differences in DNA methylation in CD, defining the disease-associated epigenome. The data strongly implicate known GWAS loci, with compelling evidence implicating MIR21 and the HLA region.</p

Generalised anxiety disorder, major depressive disorder, and their comorbidity as predictors of all-cause and cardiovascular mortality: the Vietnam Experience Study

Objective: To examine whether the 1-year prevalence of major depressive disorder (MDD), generalized anxiety disorder (GAD), and their comorbidity were associated with subsequent all-cause and cardiovascular disease (CVD) mortality during 15 years in Vietnam veterans. Methods: Participants (N = 4256) were from the Vietnam Experience Study. Service, sociodemographic, and health data were collected from service files, telephone interviews, and a medical examination. One-year prevalence of MDD and GAD was determined through a diagnostic interview schedule based on the Diagnostic and Statistical Manual of Mental Disorders (version IV) criteria. Mortality over the subsequent 15 years was gathered from US army records. Results: MDD and GAD were positively and significantly associated with all-cause and CVD mortality. The relationships between MDD and GAD and CVD mortality were no longer significant after adjustment for sociodemograhics, health status at entry, health behaviors, and other risk markers. Income was the covariate with the strongest impact on this association. In analyses comparing comorbidity and GAD and MDD alone, with neither diagnosis, comorbidity proved to be the strongest predictor of both all-cause and CVD mortality. Conclusion: GAD and MDD predict all-cause mortality in a veteran population after adjusting for a range of covariates. However, those with both GAD and MDD were at greatest risk of subsequent death, and it would seem that these disorders may interact synergistically to affect mortality. Future research on mental disorders and health outcomes, as well as future clinical interventions, should pay more attention to comorbidity