A high resolution genetic mapping of the faded (fe) gene to a region between D10mit156 and D10mit193 on mouse chromosome 10

The C57BL/6J-fe/fe mouse is a coat color mutant. The coat color of the homozygote mouse becomes progressively lighter with advancing age. The faded gene (fe) of C57BL/6J-fe/fe was mapped in a 2.0 cM distal to D10mit191 by our group. To make a high-resolution map, we used the Korean wild mouse (KWHM) for a backcross panel, which was captured in 1995 and has been maintained as an inbred line by our laboratory. In the inter-specific backcross panel (N=400), the fe gene was mapped to 1.0 cM distal to D10mit156. The gene order was defined: centromere -D10mit3/85 (1.3±0.6 cM)-D10mit155 (1.3±0.6 cM)-D10mit191 (2.0±0.7 cM)-D10mit156 (1.0±0.5 cM)-fe-D10mit193 (1.3±0.6 cM)-D10mit54 (1.0±0.5 cM)-D10mit44 (8.5±1.4 cM)-D10mit42 (10.0±1.5 cM). The measured distance between D10mit191 and D10mit 44 differed in both inter-specific (DBA/2) and intra-specific (KWHM) backcross panels (14.2 vs 13.8 cM). Taken together, our high-resolution linkage map of the fe locus from an intra-specific backcross panel will provide a good entry point to isolate the fe gene.