In the early, online edition of Genome Research, a group from the US, UK, and Colombia describes findings from a comparative genomics-based study on a form of adaptive variation in butterflies known as mimetic wing coloring. By sequencing co-mimicking Heliconius butterflies from two species and a handful of hybrid zones, researchers narrowed in on a color pattern-associated site near a gene already implicated in red color variation — an apparent regulatory region suspected of evolving by convergence in the two species distantly related species. "Using a combination of next-generation sequencing analyses, we have refined our understanding of the genetic architecture of wing pattern variation in Heliconius," they write, "and gained important insights into the evolution of novel adaptive phenotypes in natural populations."
Eusocial insects tend to share regulatory features suspected of contributing to sociality despite rapid changes to other regulatory regions and gene-coding sequences, according to a study by Arizona State University's Jürgen Gadau and colleagues. Using genome sequence data for eight eusocial insects — the honeybee and seven ant species — and 22 solitary insect representatives, the team looked at coding and regulatory patterns within each lineage and in relation to insects' sociality. In the seven ant species, representing four lineages, investigators identified a slew of novel genes. But just a few dozen genes were conserved across species, and divergence was often rampant in non-coding regions of the genomes, too, though eusocial species tended to have similar sequences within certain gene promoter regions.
Researchers from Japan and the US present evidence suggesting classical inbred mouse strains carry sequences passed down from the ancestor of "fancy" mouse species from Japan. The team re-sequenced the genomes of mice from two inbred strains developed using the Japanese mouse sub-species Mus musculus molossinus. When they compared the genomes with sequences from the mouse reference strain and other re-sequenced inbred lines, the investigators saw signs of introgression from the Japanese wild mouse lineage into the M. m. domesticus sub-species, ultimately contributing to the mosaic genomes of inbred mice, according to study authors.