Allozyme variation in a Johnston's topminnow, <i>Aplocheilichthys johnstoni</i>, population from the Zambezi River system

Abstract

Twenty five specimens of Aplocheilichthys johnstoni (Günther, 1893) were collected from the Cuando River in the Zambezi River system. Protein electrophoresis was used to analyse the genetic structure of this population. Seven of the 20 loci studied, (15% using the 95% criterion) revealed polymorphism. The heterozygosity value obtained (H O = 0.050) compare favourably to those recorded for other fish species. Observed allele frequencies deviated from expected Hardy-Weinberg proportions at the EST-3, GPD-1 and GPI-2 protein coding loci. The results from the genetic analysis of A. johnstoni are discussed in relation to its role in mosquito larval control.

Allozyme Variation in a Threatened Freshwater Fish, Spotted Murrel (Channa punctatus) in a South Indian River System

“…The excess of homozygotes is also confirmed by positive fixation index values (Table IV). Homozygote excess for allozyme has been reported quite commonly in many fish species (Engelbrecht and Mulder, 2000;Steenkamp et al, 2001). Several hypotheses have been mentioned to explain homozygote excess in fish species, including inbreeding, population admixture (Wahlund effect), or the presence of a nonexpressed allele (Appleyard et al, 2001;Ward et al, 2003).…”

Genetic variation and differentiation of wild stocks of critically endangered Puntius sarana (Hamilton) and their F1 crossbreed through allozyme electrophoresis

“…Heterozygote deficiency has been reported quite commonly in many fish species (Engelbrecht et al, 1997;Steenkemp et al, 2001). Several hypotheses have been mentioned to explain homozygote excess in fishes including inbreeding, population admixture or the presence of non-expressed alleles (Appleyard et al, 2001;Ward et al, 2003).…”