The trans-ancestral genomic architecture of glycemic traits

Glycemic traits are used to diagnose and monitor type 2 diabetes and cardiometabolic health. To date, most genetic studies of glycemic traits have focused on individuals of European ancestry. Here we aggregated genome-wide association studies comprising up to 281,416 individuals without diabetes (30% non-European ancestry) for whom fasting glucose, 2-h glucose after an oral glucose challenge, glycated hemoglobin and fasting insulin data were available. Trans-ancestry and single-ancestry meta-analyses identified 242 loci (99 novel; P < 5 x 10(-8)), 80% of which had no significant evidence of between-ancestry heterogeneity. Analyses restricted to individuals of European ancestry with equivalent sample size would have led to 24 fewer new loci. Compared with single-ancestry analyses, equivalent-sized trans-ancestry fine-mapping reduced the number of estimated variants in 99% credible sets by a median of 37.5%. Genomic-feature, gene-expression and gene-set analyses revealed distinct biological signatures for each trait, highlighting different underlying biological pathways. Our results increase our understanding of diabetes pathophysiology by using trans-ancestry studies for improved power and resolution.A trans-ancestry meta-analysis of GWAS of glycemic traits in up to 281,416 individuals identifies 99 novel loci, of which one quarter was found due to the multi-ancestry approach, which also improves fine-mapping of credible variant sets.Diabetes mellitus: pathophysiological changes and therap

The COSAC experiment on the Lander of the ROSETTA mission

International audienceThe COSAC experiment on the Lander of the ESA mission ROSETTA is aimed at the in situ investigation of matter of a cometary nucleus (P/Wirtanen) with respect to its chemical and isotopic composition. Special emphasis is put on the identification of complex organic molecules including their chirality. The instrument, presently under development, will employ for analysis a multi-column gas-chromatograph and a high-resolution TOF mass spectrometer. These instruments can be controlled from ground and used either separately or in the GC/MS coupling mode. They are suited for analysis of the natural cometary atmosphere or pyrolytically generated gas from surface or near-surface samples