Male transgenic mice weigh less, are resistant to the weight gain on a HFD, and have increased metabolic rate. (A and B) Mice were weighed once a week from birth (A) and, starting at 9 weeks of age, for 12 weeks on a HFD (B). Changes in body weight on a HFD shown as percentage of difference from day 1 of the diet. (C) Photographs of WT and transgenic (OGH-Tg) animals after 6 weeks on a HFD. (D) Measurements of body fat taken immediately before and again after 6 and 12 weeks on a HFD. (E) Metabolic rate before and after 6 weeks on a HFD. Data are expressed as mean ± SEM. *, P < 0.05, compared with WT littermate controls (one-way ANOVA).