Genes encoding the platelet-derived growth factor (PDGF) receptor and colony-stimulating factor 1 (CSF-1) receptor are physically associated in mice as in humans.
The BALB/c mouse DNA was analyzed by field-inversion gel electrophoresis to determine the orientation and distance between the beta-platelet-derived growth factor receptor-encoding gene (Pdgfr) and the colony-stimulating factor 1 receptor-encoding gene (Csfmr). It was found that the 5' portion of the Pdgfr gene was cleaved by the enzyme ClaI into two fragments. The 425-kb fragment hybridized with a 3' Pdgfr and a 5' Csfmr probe. This result shows that the Csfmr gene is 3' relative to the Pdgfr gene, and suggests that the Pdgfr and Csfmr genes are physically linked.