As the functions of the TGF-β1 C509T, G915C and T869C genes make them candidates for association with RP, a number of case–control studies were conducted to investigate the association between TGF-β1 C509T, G915C and T869C polymorphisms and risk of RP or other normal tissue complications [11]–[19]. The gene discussed is TGFB1; the disease is retinitis pigmentosa 1.