sActRIIB-mFc treated mice (open bars) had increased hindlimb skeletal muscle weights as compared to vehicle treated counterparts (solid bars: control) regardless of genotype. (A) Soleus, (B) Plantaris, (C) Gastrocnemius, (D) Tibialis Anterior, and (E) Quadriceps muscle wet weights of 4 months old WT, +/G610C, and oim/oim (n=16–25 per groups). The genotype main effect was evaluated. Values are the LSmeans±SE of the combined genotype values regardless of sex. *p<0.05; †p<0.05 vs. WT+vehicle treated mice.