The chromosomal location of the mouse mammary tumor gene Int6 and related pseudogenes in the mouse genome.

The Int6 gene is a common insertion site for the mouse mammary tumor virus (MMTV) in mouse mammary tumors. We have determined that this gene is located centromeric of the Myc protooncogene on mouse chromosome 15. In the mouse genome there are several other Int6-reactive restriction fragments that are located on mouse chromosomes 6, 11, 14, 17, and 18. Nucleotide sequence analysis of four of six of these additional Int6 fragments showed that they contain processed Int6 pseudogenes. Comparisons between the Int6 genes of the inbred mouse laboratory strains and the wild mouse species Mus spretus and Mus mus musculus indicate that some pseudogenes were present before divergence of these species and others were acquired since their separation.