A University of Minnesota-led team looks at the interplay between host genetics and microbial community composition at various body sites, using metagenomic sequences generated for the Human Microbiome Project and contaminating human reads. Based on data for 93 study participants, the researchers saw significant ties between microbiome membership and host genetics at 10 body sites — associations that tended to reflect activity by host immune pathways and host pathways implicated in conditions such as obesity or inflammatory bowel disease. "Our results highlight the role of host genetic variation in shaping the composition of the human microbiome," the study's authors say, "and provide a starting point toward understanding the complex interaction between human genetics and the microbiome in the context of human evolution and disease."
The National Cancer Institute's Stephen Chanock and colleagues present evidence suggesting that parts of the genome containing common alleles linked to cancer susceptibility are no more prone to somatic mutation than non-cancer-related regions of the genome. After identifying cancer susceptibility sites through a literature search, the team scrutinized somatic mutation patterns in the cBioPortal database and data generated for the Cancer Genome Atlas project. Results from the analysis suggested that the common cancer susceptibility regions usually had background mutation rates resembling other parts of the genome.
Researchers from the University of California, Irvine, the California Institute of Technology, and elsewhere describe efforts to sequence and analyze the draft genomes and transcriptomes of Steinernema nematode worms known for their ability to parasitize insects. The team started by producing a draft genome sequence for Steinernema carpocapsae. By re-sequencing four more species — S. scapterisci, S. monticolum, S. feltiae, and S. glaseri — and comparing sequences from all five Steinernema to one another, the study's authors uncovered gene family expansions suspected of contributing to parasitism. Meanwhile, their transcriptome data pointed to genes expressed during certain stages of the Steinernema life cycle.