Inheritance of isozyme phenotype at three loci in the freshwater snail, Goniobasis proxima: mother-offspring analysis and an artificial introduction.

A good deal of interest has recently focused on the genetics of Goniobasis populations, with isozyme frequencies often a primary tool. I sampled 72 Goniobasis proxima from a population naturally polymorphic at three enzyme loci, Gpi, Opdh, and Est, reared each in isolation, and electrophoretically analyzed 14 sibships produced. Since females apparently mate but once in their lifetimes, it was possible to infer paternal genotype and demonstrate that inheritance is Mendelian at these three loci. The three loci appear to assort independently. A pair of G. proxima populations fixed for alternative alleles at the three loci has been introduced into a small spring. Triply heterozygous F1 hybrids have been recovered, although at a low frequency.