In the March issue of Genome Research, work led by Evan Eichler describes the first systematic and genome-wide analysis of segmental duplications and CNVs in the modern domesticated dog, Canis familiaris. Using tiling arrays that covered all predicted segmental duplications, Eichler's team performed array CGH across 17 breeds and a gray wolf, identifying 3,583 CNVs. They found that these CNVs span 429 genes that are involved in many biological processes such as olfaction, immunity, and gene regulation.
In advance online publication, scientists from the MRC Laboratory of Molecular Biology studied the genome-wide effects of trans- and cis-regulatory mutations on gene expression. Comparing the "genomic neighborhood" of orthologous genes in human and chimps with their different gene expression patterns, they found that "genes with altered neighborhood are more likely to undergo expression divergence than genes with conserved neighborhood" and that in addition to other mechanisms, "change in genomic neighborhood is an important factor that drives transcriptome evolution."
Also in early online, researchers looked for positive selection across 53 populations, using genotype data from the Human Genome Diversity-CEPH Panel. Among other things, they found possibly new targets of selection for several genes in the NRG–ERBB4 developmental pathway in non-African populations and for genes involved in susceptibility to type II diabetes.
Cornell biologists examined the evolution of Campylobacter, a genus that includes several important human and animal pathogens. Examining the genome sequence data across eight species comprising 647 genes, they estimate that 92.5 percent of the non-recombinant core genome is under positive selection on at least one lineage and that the same gene is often under positive selection on multiple lineages. They suggest that this selection occurs due to different species competing for the same resources within the gastrointestinal tract.