Analysis of host genetic control of scrapie-induced obesity.

The potential for induction of obesity during the preclinical phase of scrapie disease in mice was previously shown to be a function of both the strain of scrapie and the strain of inbred mouse. In the present study, host control of obesity induction by a scrapie strain was examined to determine if the effect were dependent on a single gene or multiple genes. The approach used was assessment of the pattern of weight induction in F1 and F2 crosses of parental inbred mouse strains that did or did not show a weight increase with a specific scrapie strain. Analyses of these data indicated that the induction of obesity was controlled by multiple host genes. In an unrelated observation, there was a correlation between the incubation period of a strain of scrapie in F2 generation mice and their coat color, i.e., the average incubation period of yellow-brown mice was significantly less than those of either black or white mice.