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.
Wash Your Hands Before and After You Read This
Sandra Porter has a few posts on using digital biology to take a gander at the swine flu that's all the rage. In the first, she uses the NCBI Influenza Virus Resource to see which animals are influenza hosts (the list includes the blowfly, which Porter doubts). Then, she uses the same tool to see which strains have infected certain animals. Next, Porter points out the latest swine flu sequences in GenBank from California, New York, and Texas. She uses that to build phylogenetic trees with that data and more from a 2007 outbreak at an Ohio county fair. They indicate that "the California swine virus is most closely related to a swine flu virus from Ohio" -- though she is refining her work based on feedback on her site. At Aetiology, Tara Smith looks at a new paper on the 2007 Ohio outbreak and Porter's work. "Does this mean the virus came from these Ohio pigs? *Well, no, not necessarily*," she writes, adding that a lot of data is still missing, such as sequences from the Mexican patients and pigs.
In related news, the first US death due to swine flu has been reported in Texas, where a 23-month-old child died. Some reports say that more people in New York City, where a large cluster was first seen in the US, have suspected cases of swine flu. Also, US officials say that it will take until November at the earliest -- and more likely January -- to have enough vaccine on hand to protect everyone in the US from swine flu.