A new mutant at the Dystrophia muscularis (dy) locus in the SM strain of mice.

Muscular dystrophy was found in the SM strain of mice. This defect was shown to be caused by a single autosomal recessive gene allelic with the genes at the dy locus. The dystrophic SM mice may provide a useful animal model for human muscular dystrophy, because SM strain has been selected for small body size and carries rare alleles at several loci.