Genetic control of glucokinase activity in mice.

Inbred strains of mice were surveyed for liver glucokinase activity. Mice of all strains studied could be distributed into three groups with high, intermediate, and low levels of enzyme activity. Genetic analysis using crosses and backcrosses with prototype high (C3H/HeJ) and low (RF/J) strains revealed that glucokinase activity was controlled by a single gene. The name "glucokinase" and gene symbol Gk are suggested for this gene. The Gka allele designates the strain with high glucokinase activity, while Gkb represents the allele in the strain with the low enzyme activity. The interaction of fasting and diabetes on the activity of glucokinase in these two strains is described.