Effects of contaminants on the frequencies of allozymes in populations of the central stoneroller

Abstract

Allele and genotype frequencies for allozymes of phosphoglucomutase (PGM) differed significantly between populations of the central stoneroller (Campostoma anomalum, Rafinesque) collected from sites above and below impact from industrial activities. The frequencies of the PGM‒A allele and PGM‒AA and PGM‒AB genotypes were significantly less in populations of stoneroller minnows collected from impacted sites than in populations upstream of impact. Stonerollers with these sensitive PGM genotypes and stonerollers with genotypes of malate dehydrogenase MDH‒BB were more sensitive to the toxic effects of copper sulfate than other genotypes under laboratory conditions. These results suggest that individuals with certain allozymes may be more sensitive to the toxic effects of environmental contaminants than those with other genotypes. Selection or elimination of individuals with sensitive genotypes by contaminants may result in a narrowing of genetic diversity in populations and thus increase the susceptibility of these populations to further stress. Electrophoretic determination of genetic structure in fishes appears to be sensitive to changes in water quality and may be a useful tool for monitoring the health of aquatic populations.

Allozyme polymorphisms in horseshoe crabs, Carcinoscorpius rotundicauda, collected from polluted and unpolluted intertidal areas in Peninsular Malaysia

“…This result is in line with the findings of Theodorakis and Shugart (1997) as well as Yap et al (2004) where measures of genetic diversity indicated that the contaminated sites were more similar to one another than to the non-contaminated sites. Many researchers and ecotoxicologists had suggested that monitoring changes in population genetic structures by allozyme analysis is a valuable and useful population-level biomarker of heavy metal contamination (Lavie and Nevo 1986;Ben-Shlomo and Nevo 1988;Gillespie and Guttman 1989;Diamond et al 1989;Yap et al 2004;Yap and Tan 2007). In addition, the dendrogram drawn based on Nei's (1978) genetic identity values was in agreement with the SLBGMED dendrogram of heavy metals in the non-resistant fraction of the sediments obtained by SET (Fig.…”

Genetic diversity and adaptability ofSarotherodon melanotheron(Cichlidae) in coastal ecosystem

“…Sensitivity of allozymes to environmental stress seemed to reflect the adaptive nature of the individuals (MORAGA et al 2002). Anthropogenic factors such as pollution appeared to favour the selection of individuals with particular genetic composition within the fish populations through differential survival of the species (THORPE et al 1981;SMITH et al 1983;GILLESPIE & GUTTMAN 1989;DUAN et al 2001). Moreover, KOPP et al (1994) reported that genotypes that survived an exposure to pollution or salinity can represent the most tolerant individuals in a stressful environment.…”

“…Moreover, KOPP et al (1994) reported that genotypes that survived an exposure to pollution or salinity can represent the most tolerant individuals in a stressful environment. CHAGNON & GUTTMAN (1989) and GILLESPIE & GUTTMAN (1989) reported that the degree of genetic variation maintained by a population can be the proof of its ability to survive a future environmental decay. The observed differences in genetic diversity between populations from a disturbed environment with varying degrees of stress may also be the result of other factors.…”

Genetic variation in two land snails, Cepaea nemoralis and Succinea putris (Gastropoda, Pulmonata), from sites differing in heavy metal content

“…Chagnon & Guttman, 1989a;Duan et al, 2000;Theodorakis, 2003), and (iv) allozyme loci may be good bioindicators for metal toxicants as these may have direct effects on enzyme structure and function (e.g. Chagnon & Guttman, 1989a, b;Gillespie & Guttman, 1989). Hence, allele or genotype frequencies may be associated with the degree of pollution in any given environment (Gillespie & Guttman, 1999;D'Surney, Shugart & Theodorakis, 2001).…”