Genetic control of sensitivity to Moloney leukemia virus in mice. II. Mapping of three resistant genes within the H-2...

The level of viremia and the appearance of leukemias were studied after inoculation wtih Moloney leukemia virus (M-MuLV) in different H-2 congenic strains of mice. The viremia was regularly measured on individual mice with a radioimmunoassay of the major internal virion component p30. Three genes within the major histocompatibility complex controlled the level of circulating virus. Two of them, called Rmv.1 and Rmv.2, appear to be located in the I region, respectively, in the IA, and the IC-S or G regions. The third gene, Rmv.3, was mapped to the D end of the complex in the D or T region. Crosses between resistant and sensitive strans demonstrated that the H-2 associated resistance was inherited as a dominant or semi-dominant Mendelian trait. Rmv.1, Rmv.2, and Rmv.3 were shown to complement for resistance in trans when the hybrids between sensitive strains were examined. A good correlation was found between viremia and the appearance of leukemias, the most viremic strains being also the most leukemic. Nevertheless, additional non-H-2 genes must control viremia and/or the appearance of leukemia since, despite high levels of viremia, some sensitive strains do not become leukemic.