In the early, online edition of Genome Research, an international team turned to integrated genotyping to tally up genome architecture variation in the 205 sequenced inbred lines included in the Drosophila melanogaster Genetic Reference Panel (DGRP). Based on information at nearly 5 million SNPs and almost 1.3 million more non-SNP variants, for example, the researchers found that deletions were more common than insertions in the fruit fly genomes though deletions were subject to more pronounced purifying selection. They also uncovered more than a dozen inversion polymorphisms in the Drosophila genomes and a few instances of insertions traced back to the beneficial bacteria Wolbachia, which was found in around half of the DGRP lines.
The University of Bath's Ruth Massey led a group from the UK, Turkey, the US, and Sweden that used a genome-wide association approach to consider toxicity and adhesiveness amongst isolates of methicillin-resistant Staphylococcus aureus, or MRSA. Although the researchers detected fairly modest variability in the adhesiveness of the strains, they determined that toxicity varied markedly between isolates — differences that could be predicted, in part, by a set of SNPs, insertions, and deletions influencing that toxicity. Our sister publication GenomeWeb Daily News has more on the study, here.
Researchers from the Netherlands, the US, and Australia found dramatically diminished hematopoietic stem cell sources and reduced telomere lengths when they did deep whole-genome sequencing on white blood cells from a 115-year-old woman. The team's genome sequencing data indicated that the woman's white blood cells contained some 450 or so somatic changes not found in DNA from her brain tissue, though many or all of the genetic glitches detected were deemed harmless, passenger mutations. But the allele frequencies found indicated that almost all of the white blood cells interrogated in the woman's blood samples stemmed from two hematopoietic stem cell clones that were related to one another, pointing to cell division limits for hematopoietic stem cell populations. For more details, check out GWDN.