Identification of genes associated with orange spot formation in the guppy, Poecilia reticulata

In the guppy, Poecilia reticulata, a model system for research on sexual selection, females prefer males possessing larger and more highly saturated orange spots as their mates. We estimated the expression levels of genes in male guppy skins using RNA-seq to reveal the genetic basis of orange spot formation. First, we compared gene expression levels between the skins of orange spots (orange skin) and those without any color spots (dull skin) and identified gene expression patterns specific to the orange skin. Second, the gene expression levels of whole trunk skins were compared among the three developmental stages to detect genes that change expression levels depending on orange spot development.