Individuals with chronic periodontitis tend to have distinct microbial communities in deep pockets around their teeth compared to those at healthier sites closer to the surface, according to a PLOS One study by Virginia Commonwealth University researchers. The team used 16S ribosomal RNA gene sequencing to characterize paired shallow and deep oral microbiome samples from 88 individuals with chronic periodontal disease. Along with microbiome shifts between the shallow and deep dental pocket sites in each person — which varied with factors such as smoking status or race — the analysis pointed to possible differences between the collections of bugs contributing to cavities and those linked to periodontal disease.
A PLOS Genetics study looks at genetic variants influencing traits such as height, weight, body fat, or waist and hip measurements that differ between men and women. Members of the international Genetic Investigation of Anthropometric Traits, or GIANT, consortium drew on data for 133,723 individuals for a meta-analysis aimed at finding sexually dimorphic genetic contributors to these and other anthropometric traits. That analysis, followed by a validation study involving more than 137,000 other individuals, led to variants at seven loci showing significant ties to waist-related traits in women but not men.
In PLOS Neglected Tropical Diseases, French researchers take a look at genetic patterns found in Madagascar's black rats — an animal reservoir for the plague-causing pathogen Yersinia pestis. The team used microsatellite markers to gauge genetic structure and diversity in nearly 1,300 animals in four black rat populations sampled in mountainous or flat parts of the island, looking at how these profiles corresponded to the serotype of Y. pestis detected in the rats when the pathogen was present. Genetic structure was highest for rats living in mountainous regions of Madagascar, study authors note, though more research is needed to understand genetics in the plague reservoir animals relates to the pathogen's presence and spread.