f1 hybrids of strain sts and the two strains c3hf and balb/c show high incidences ( sts x c3hf f1 , 90 % ; sts x balb/c f1 , 60 % ) , but the age at which tumors appear ( 476 and 604 days , respectively ) is much higher , suggesting that more than one gene is involved in this type of hormonal carcinogenesis of the mammary gland in mice .
C0037556
sts
C0027651
tumors