In PLOS Genetics, researchers from Yale University, Peking University, and the University of Washington report on findings from a study suggesting ties between immune-related DNA elements and susceptibility to late-onset Alzheimer's disease. The team began by using a statistical framework called GenoSkyline-Plus to narrow in on tissue-specific regulatory clues to complex conditions based on data from epigenetic and genome-wide association studies. From there, it focused on loci implicated in late-onset Alzheimer's disease, folding in epigenomic and transcriptomic data for diverse cell types to find overlap between variants associated with Alzheimer's and variants contributing to the function of monocyte cells, liver tissue, and innate immune pathways, for example.
Another PLOS Genetics paper considers population patterns gleaned from genome sequences for more than a dozen individuals who lived in present-day Portugal some 1,400 years to 4,200 years ago, during the Middle Neolithic and Middle Bronze Ages. There, investigators took a closer look at historical migrations through the Iberian region by sequencing 14 ancient individuals and analyzing imputed diploid versions of those genomes alongside previously described sequences from other ancient Europeans. "While discontinuity is evident in the transition to agriculture across the region, sensitive haplotype-based analyses suggest a significant degree of hunter-gatherer contribution to later Iberian Neolithic populations," the authors write, noting that a "more subtle genetic influx is also apparent in the Bronze Age.
Finally, a team from Belgium and Benin explores the bacterial diversity present at Buruli ulcer sites for a paper appearing in PLOS One. Using 16S ribosomal RNA sequencing, the researchers characterized skin microbial community composition for lesions in individuals with Buruli ulcer, an infectious disease common to West and Central Africa that's caused by Mycobacterium ulcerans bacteria. Comparing microbes at five Buruli ulcer with those in five non-Buruli ulcer skin lesions and three healthy skin samples, they saw similar overall diversity in both types of lesions. Even so, there appeared to be a slight uptick in the representation by Bacteroidetes bacteria and obligate anaerobic bacteria at the Buruli ulcer sites.