Top two IPA networks from analysis of all genes differentially expressed in PvH. The red shading indicates genes that show decreased expression in horned animals versus polled individuals while green is a measure of up-regulation in polled versus horned. The colour intensity is proportional to the level of up- or down-regulation. (A) is the network of genes involved in hair and skin development. (B) Skeletal and muscular system development and function and tissue morphology.