Abstract
Electrophoretic variations of enzymatic and non-enzymatic proteins were investigated in 8 populations of the loach M. anguillicaudatus. The cathodic Hb and the muscle protein in the region were polymorphic, in addition to the 5 polymorphic proteins previously reported (the anodic Hb, muscle protein in the region III, 6-phosphogluconate dehydrogenase, phosphoglucomutase and aspartate aminotransferase). The muscle proteins in the regions I, IV and V were monomorphic. The values of genetic distances between loach populations, calculated over 10 loci, indicated that M. anguillicaudatus should be classified into 2 local [Japanese] races.