Mouse mammary tumor virus (MMTV)-like DNA sequences in the breast tumors of father, mother, and daughter

Background The diagnosis of late onset breast cancer in a father, mother, and daughter living in the same house for decades suggested the possibility of an environmental agent as a common etiological factor. Both molecular and epidemiological data have indicated a possible role for the mouse mammary tumor virus (MMTV), the etiological agent of breast cancer in mice, in a certain percentage of human breast tumors. The aim of this study was to determine if MMTV might be involved in the breast cancer of this cluster of three family members.