An international team led by investigators at the University of California, San Diego, used whole-genome sequencing to search for clues to the genetics of altitude adaptation in Ethiopian highlanders. The researchers' whole-genome re-sequencing efforts focused on 13 individuals who were native to high-altitude locales in Ethiopia, including six from a population living on the Bale Plateau and seven from Chennek field in the Simien mountains. Analysis of the sequences revealed several genomic sites with signs of selective sweeps such as diminished diversity. Among them was a chromosome 19 region containing eight protein-coding genes, which the team interrogated in more detail in a fruit fly model — experiments that hinted at low oxygen survival roles for at least three of the genes.
Another UCSD-led group looked at how well self-reported ancestry coincided with array-based genetic ancestry markers in individuals enrolled in the National Children's Study. Using blood samples from almost 650 participants in the prospective epidemiological effort, the investigators used exome arrays to assess ancestry and genetic diversity of individuals participating in the study. The team's comparison between variant in the samples and patterns in 1000 Genomes Project data suggested self-reported ancestry was accurate for some 99 percent of participants. "[O]ur data indicate that despite the complexity of the US population, individuals know their ancestral origins," the study's authors write, "and that self-reported ethnicity and race is a reliable indicator of genetic ancestry."
The Helmholtz-Institute for Biomedical Engineering's Wolfgang Wagner and colleagues present evidence of epigenetic signatures of aging in human blood samples. The team used array-based methylation profiling to look for shifts in cytosine methylation association with aging blood — a search that led to 102 apparent age-related methylation sites. When they scrutinized these sites in more detail, the researchers found that methylation patterns at these marks could be reversed during induced pluripotent stem cell development. Through bisulfite sequencing in another 151 blood samples, they saw that just three of the methylation sites may provide a peek at blood age within roughly a five year range.