A large-scale genome-wide association study in Japanese individuals identifies dozens of new susceptibility loci across various disease states, highlighting the importance of such studies in non-European populations. As reported in Nature Genetics this week, an international research team led by scientists from the Riken Center for Integrative Medical Sciences performed the GWAS with 212,453 Japanese people across 42 diseases common in the BioBank Japan Project including cancers, cardiovascular diseases, and infectious diseases. Among the findings were 320 independent signals in 276 loci for 27 diseases, with 25 novel loci. Notably, for three of these loci East Asian-specific missense variants were identified as candidate causal variants. "Currently, large-scale genetic studies are dominated by European-descent samples and fail to capture the level of diversity that exists globally," the study's authors write. "Our study contributes to broadening the population diversity in genetic studies and should potentially mitigate the problems originating from this imbalance."
While modulation of the function and metabolism of transfer RNAs (tRNAs) is a critical aspect of translation in changing cellular conditions, the structure, location, and extent of such modifications have been systematically cataloged in very few organisms, primarily due to technical limitations. To address this issue, scientists from Harvard Medical School and the Massachusetts Institute of Technology have developed an approach — described in this week's Nature Chemical Biology— that couples high-throughput tRNA sequencing for the prediction of modified sites with RNA mass spectrometry-based identification of tRNA modifications. They use their method to profile tRNA modifications in Vibrio cholerae, a disease-causing bacteria where tRNA modifications have not been charted, and to uncover a species-specific modification and a new tRNA modification, and to find evidence for an RNA editing process not previously observed.