DEPs involved in tuberculosis, neuroactive ligand–receptor interaction, MAPK signaling pathway, HTLV-I infection, graft-versus-host disease, autoimmune thyroid disease and allograft rejection, such as BF2, DHX36, CNPY3, and HYAL1 were compared in spleen development between Pengxian yellow chickens and Tibetan chickens (Table 3) (Figure 5 (C)). Here, HYAL1 is linked to autoimmune thyroid disease.