Isozyme variation within and among population of Microsporum species

Isozyme variation among 54 isolates of Microsporum canis, 18 Microsporum co okei isolates and two Diheterospora isolates were studied using starch gel electrophoresis. Of eight enzymes examined, four were polymorphic (EST, G6P , MDH and PEP), having from two to four electrophoretic forms. Within each species, consistent and reproducible isozyme patterns of the eight enzyme s ystems were obtained. Phenotypic diversity (H) in M. canis was higher than in M. cookei (H=0.459 and H=0.408 respectively), but phenotypic differentia tion of M. canis isolates from different geographical regions (Auckland, We llington and Palmerston North, New Zealand) was low, with a proportion of t otal diversity (G(st)) of 0.151 found among the localities. The results sug gest that the isolates of M. canis from different geographical regions are closely related, supporting the theory of a common lineage.