Multiparous transgenic female mice expressing NRG1, a ligand for ERBB3 and ERBB4, under control of the MMTV promoter also develop adenocarcinomas in the mammary glands at a median age of 12 months [51], suggesting ErbB4 to be contributing to neuregulin-induced carcinogenesis. This evidence concerns the gene ERBB4 and adenocarcinoma.