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Published on: September 10, 2020
Heterosis associated with DOPA-oxidase dimorphism in Culex pipiens
1Biomedical Research Laboratory, Southern University, Shreveport, LA 71107.
Abstract:
1. Isozyme phenotypes were used to deduce genotypes at a dimorphic DOPA-oxidase locus in a laboratory population of Culex pipiens. The frequencies of homozygotes and heterozygotes at the inception and termination of laboratory colonization were compared. 2. Co-dominant alleles F and S condition the fast and slow isozymes (allozymes) respectively at this enzyme locus. 3. The expected and observed ratios of heterozygotes (FS) to homozygotes (FF and SS) were 50:50 and 64:36 respectively for 50 pairs of parents. 4. The observed and statistically significant excess of heterozygotes is taken as evidence of heterosis and the heterotic maintenance of enzyme dimorphism at this locus.
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