DETECTION OF HEAT-STABILITY VARIANTS IN GPI ISOZYMES OF GOLDFISH AND CRUCIAN CARP

A combination of electrophoretic and heat denaturation techniques was used to identify the gene loci and alleles of the isozymes in goldfish and crucian carp. Heat denaturation experiments revealed different he at stabilities among three loci (Gpi-1, Gpi-2*, and Gpi-3*) encoding glucosephosphate isomerase (GPI) in goldfish and crucian carp. The hea t stability differences were found in all the three loci examined. Cro ss experiments indicated that the observed differences among alleles a t each locus in heat stability are controlled by a single incomplete d ominant gene. Moreover, the heat stability alleles demonstrated a dive rgence in Gpi-1 and Gpi-2* loci between goldfish and crucian carp. Th e heat denaturation technique was thus useful for the revelation of hi dden genetic variations of isozymes.