Genomic and phenotypic insights from an atlas of genetic effects on DNA methylation

DNA methylation quantitative trait locus (mQTL) analyses on 32,851 participants identify genetic variants associated with DNA methylation at 420,509 sites in blood, resulting in a database of >270,000 independent mQTLs.Characterizing genetic influences on DNA methylation (DNAm) provides an opportunity to understand mechanisms underpinning gene regulation and disease. In the present study, we describe results of DNAm quantitative trait locus (mQTL) analyses on 32,851 participants, identifying genetic variants associated with DNAm at 420,509 DNAm sites in blood. We present a database of >270,000 independent mQTLs, of which 8.5% comprise long-range (trans) associations. Identified mQTL associations explain 15-17% of the additive genetic variance of DNAm. We show that the genetic architecture of DNAm levels is highly polygenic. Using shared genetic control between distal DNAm sites, we constructed networks, identifying 405 discrete genomic communities enriched for genomic annotations and complex traits. Shared genetic variants are associated with both DNAm levels and complex diseases, but only in a minority of cases do these associations reflect causal relationships from DNAm to trait or vice versa, indicating a more complex genotype-phenotype map than previously anticipated.Molecular Epidemiolog

Progress in Modeling of Pre-Ionization and Geometric Effects on a Field-Reversed Configuration Plasma Thruster

In recent years, compact toroid (CT) plasma (e.g., field-reversed configurations, plasmoids, or spheromaks) has been considered for propulsion applications. A limited number of studies have been conducted thus far with each investigating different aspects of CT plasma. The current investigation into CT plasma documented here focuses on developing a thruster concept to assess the efficiencies of CT plasma formation and acceleration. The assessment consists of developing MHD simulations that model a typical CT test article. The pre-ionization geometry and device geometry parameters are varied in these simulations to determine the efficiencies