(A) The bars represent total body weight for the ages indicated for male (left graph) and female (center graph) PGC-1α+/+ and PGC-1α−/− mice. The body weight (BW) of the 1-wk-old PGC-1α−/− mice was normalized to that of PGC-1α+/+ littermates, which was assigned a value of 100 (left axis). For the 3-, 18-, and 24-wk time points, absolute weights of PGC-1α−/− mice were compared to age-matched controls (right axis). Percent fat as determined by DEXA scanning for PGC-1α+/+ and PGC-1α−/− mice (right graph). The results represent n = 4 (males) and n ≥ 11 (females) for each genotype at 24 wk. * p < 0.05 compared to corresponding PGC-1α+/+ mice.