Characterization of Allozyme Null and Low Activity Alleles from Two Natural Populations of DROSOPHILA MELANOGASTER.

Null and low enzyme activity alleles recovered from two natural populations were analyzed for a number of genetic and biochemical properties. Analysis of 58 mutations at 14 loci showed that all but one allele were genetically viable and fertile, four alleles were associated with chromosome rearrangements, 28 alleles retained some enzyme activity, 13 alleles formed an active heterodimer with active alleles and five alleles showed partial interallelic complementation. Available evidence indicates that this sample includes mutations resulting from lesions in both coding and regulatory sequences. Certain mutations may be caused by transposable element insertions.