In PLOS Genetics, a team led by investigators at the University of Michigan explore the possibilities and limitations of applying cancer polygenic risk scores (PRS) developed with European participant data to other populations until more diverse genome-wide association data becomes available. After putting together PRS for prostate cancer and breast cancer with genetic and electronic health record data from European UK Biobank project participants, the researchers assessed the scores in participants of African, East Asian, South Asian, or European ancestry, identifying some predictive potential for the PRS despite ancestry-related risk differences. "Taken together, our findings suggest that cross-ancestry cancer PRS can be useful for risk stratification, especially when there is a lack of well-powered diverse cancer GWAS," they write. "However, caution needs to be applied to the interpretation and application of such genetic risk predictors as they can be prone to multiple sources of bias." GenomeWeb has more on this, here.
For a paper in PLOS Neglected Tropical Diseases, researchers in Colombia, the UK, Vietnam, and Argentina consider the genetic diversity of typhoid fever-causing Salmonella enterica serovar Typhi representatives in Colombia. Using whole-genome sequencing and conventional pulse field gel electrophoresis-based genotyping, the team assessed 77 isolates collected in Colombia from 1997 to 2018, uncovering signs of two main endemic S. Typhi clades with relatively low levels of antimicrobial resistance in the country. "Our study provides the first enhanced insights into the molecular epidemiology of S. Typhi in Colombia, using [whole-genome sequence (WGS)] data for the first time to investigate the population structure in Colombia and identifying predominant circulating genotypes," the authors write, adding that the study "demonstrates that routine surveillance with the integration of WGS is necessary not only to improve disease burden estimates, but also to track the national and regional transmission dynamics of S. Typhi."
A team from Rochester General Hospital and Drexel University College of Medicine outlines a potentially protective role for Corynebacterium bugs in the nasopharyngeal microbiome of children with Streptococcus pneumoniae infections. Using nasopharyngeal samples collected from 96 children with or without S. pneumoniae infections at the ages of six-months-old and/or a year old, the researchers used 16S ribosomal RNA sequencing to look at the microbial community representatives that coincided with S. pneumoniae infection or other conditions. Their results suggest that lower-than-usual levels of S. pneumoniae colonization tend to correspond with the presence of Corynebacterium and vice versa, prompting follow-up microbial co-culture experiments that pointed to reduced S. pneumoniae growth in the presence of two Corynebacterium species.