Fructose bisphosphatase isozymes of the mouse. I. Inheritance.

Electrophoretically detectable polymorphisms of fructose bisphosphatase (EC 3.1.3.11) have been found in the mouse. One polymorphism, found among inbred strains of Mus musculus and feral animals, affects the isozymes found in the muscle and in most other tissues examined but is not expressed in kidney, liver, or testis. These tissues have other electrophoretically distinct isozymes which are monomorphic in Mus musculus but are present as a different electromorph in the sympatric species Mus spretus. Breeding data have established that the genetic control of the muscle enzyme is expressed by an autosomal structural locus Fbp-1 which is distinct from that expressing the liver, kidney, and testis enzyme, Fbp-2. The organ-specific expression of the two loci suggests possible functional differences between the two products.