The relative expression (target/ YWHAZ) of MHCα, RYR2, SERCA2, and THRα genes in the right ventricle tissues was higher in PHS group of broilers than control group at 21 d (P < 0.05).The amounts of this increase were 83.7%, 50%, 90.9%, and 50%, respectively in the mentioned genes. This evidence concerns the gene THRA and Pallister-Hall syndrome.