[A new mutant in the mouse: peroneal muscular atrophy (author's transl)].

An anomaly of the hind limb has been found in the process of inbreeding of the CF#1 strain. The affected mouse showed a club foot at birth and unusual gait by a dropped foot in the adult. The growth of the affected mouse was slightly delayed in comparison with normal littermates, but reproductive performance was almost normal in both sexes. Anatomical and pathological studies revealed the atrophy of the peroneal muscle group and absence of the common peroneal nerves. The genetical studies showed that this anomaly was mainly controlled by a single autosomal recessive gene. The penetrance and expressivity of the gene was complete in the original or related strains, but incomplete in the other genetic backgrounds. This major gene has been named peroneal muscular atrophy (gene symbol: pma).