HG9
CAST alleles in the proximal region of MMU9 were previously found to be linked with an increase in body fat percentage and a decrease in femur length [24]. The effects appeared to be the result of two linked QTL, Carfhg2 at 10 cM and Feml2 at 20 cM, instead of one pleiotropically impacting both traits (Table 1). In support of this, the increase in fat was dependent on hg; however, differences in femur length were not [24].
In confirmation of Carfhg2 all measures of adiposity in HG9 mice were increased relative to control mice; except MFP in both sexes and BMI in males (Table 5). In males, GFP, RFP, FFP and AI were increased by 29.0%, 51.2%, 42.9% and 30.0%, respectively. In females these increases were much larger. The same measurements were increased by 68.8%, 99.4%, 69.7% and 57.3%, relative to HGC females. A 2.9% and 3.6% reduction in male and female NA, respectively, was also detected. This was expected since NA was previously found to be an excellent indicator of femur length (R2 = 0.88) in HG mice [27] and as noted above this region contains the Feml2 QTL [24]. These data confirm the effects of Carfhg2 on adiposity and Feml2 on length and indicate the isolated effects of Carfhg2 are more significant than originally observed.