Cellular homologs of the avian erythroblastosis virus erb-A and erb-B genes are syntenic in mouse but asyntenic in man

Avian erythroblastosis virus, a retrovirus that causes erythroblastosis and sarcomas in infected birds, possesses two host cell-derived genes [viral (v) erb-A and erb-B]. Although v-erb-B seems to be responsible for oncogenic transformation, v-erb-A might have an enhancing effect on transformation. In chickens, the natural host for avian erythroblastosis virus, cellular (c) erb-A and erb-B genes appear to be unlinked, but their chromosomal locations in other species are unknown. To ascertain the chromosomal location of c-erb genes in man and mouse, we analyzed interspecies somatic cell and microcell hybrids by Southern filter hybridization techniques using specific v-erb-A and v-erb-B probes. We found c-erb-A sequences on human chromosome 17 (17p11 → qter) and located c-erb-B on human chromosome 7 (7pter → q22). In contrast, both c-erb-A and c-erb-B reside on mouse chromosome 11.