Category VI genes, such as Janus kinase 1 (JAK1), Janus kinase 2 (JAK2) and tyrosine kinase 2 (TYK2) were up-regulated in BH compared with BC and have a role in wound healing and tissue regeneration [58], in agreement with categories I and IV genes, which indicates that muscle damage is much more important in heat-stressed broilers than BC, LC and LH. This evidence concerns the gene TYK2 and breast cancer.