Chromosome-Scale Selective Sweeps and Genomic Diversity in C. elegans
Andersen, Gerke et al., Nature Genetics
Researchers at Princeton University and elsewhere discuss the effects of chromosome-scale selective sweeps on genomic diversity in Caenorhabditis elegans. Taking a high-throughput selective sequencing approach on a collection of 200 wild C. elegans strains, the team found that the nematode's "genome variation is dominated by a set of commonly shared haplotypes on four of its six chromosomes, each spanning many megabases." Further, the team reports on its population genetic modeling experiments, which showed that "this pattern was generated by chromosome-scale selective sweeps that have reduced variation worldwide; at least one of these sweeps probably occurred in the last few hundred years," it writes.
This Week in Science
In news this week, scientists and universities are asking US Congress "not to expand a $2 billion research program for small businesses" because it would likely cut money that could otherwise go toward research projects.
In a policy forum article, lead author Sandra Soo-Jin Lee from Stanford looks at quality standards in genetic ancestry testing, ultimately calling for government regulation of this field. Blogger Blaine Bettinger offers his thoughts on the article here.
A paper from EMBL researchers looks at Polycomb group proteins in Drosophila, finding a significant role for O-GlcNAc glycosylation in gene silencing performed by these proteins. Jeffrey Simon at the University of Minnesota has a perspectives piece on the work.
Scripps' Reza Ghadiri is senior author on a paper introducing a family of oligomers that "efficiently self-assembles by means of reversible covalent anchoring of nucleobase recognition units onto simple oligo-dipeptide backbones [thioester peptide nucleic acids (tPNAs)] and undergoes dynamic sequence modification in response to changing templates in solution," according to the abstract. The team notes that the characteristics of the peptide nucleic acids "might prove advantageous for the design or selection of catalytic constructs or biomaterials that are capable of dynamic sequence repair and adaptation."