Mutations in the genes encoding dystrophin and its associated proteins, the sarcoglycans,
lead to muscular dystrophy in humans and in mouse models. In the presence of identical
gene mutations, the muscular dystrophy phenotype can be highly variable. Using a mouse
model of limb girdle muscular dystrophy engineered with a null allele of γ-sarcoglycan, we
bred the identical γ-sarcoglycan mutation into four different genetic backgrounds. We found
that the γ-sarcoglycan mutation is least severe in the129SV/J (129) strain and most severe …