Family heterozygosity and progeny body length in pink salmon Oncorhynchus gorbuscha (Walbaum)

Abstract

The relationship between multiple-locus heterozygosity at eight polymorphic enzyme loci and progeny body length was examined in 20 experimental pink salmon families differing in parental heterozygosity. It was shown that: (1) the effect of individual heterozygosity on body length within the families was not statistically significant; (2) a considerable part of the between-family component of variance of body length was largely attributed to the differences in family heterozygosity; (3) there was no association between the mean family heterozygosity and the coefficient of variation of body length. In the groups of families with the low, intermediate and high heterozygosity the highest value of mean progeny body length was recorded in the intermediate heterozygosity group. There was no significant effect of heterozygosity at single loci on these differences among families. The results are explained by the hypothesis of epistasis and the hypothesis of maintenance of an optimal heterozygosity level in populations.

The Effect of Enzyme Heterozygosity on Growth in a Strictly Outcrossing Species, the Self-Incompatible Arabis Petraea (Brassicaceae)

“…This in-crease in effect conflicts with the view that maternal effects decrease over time, but the reason may be the increased statistical power in detecting differences at day 104 as compared with days 41 and 61, because the measure used at day 104 is more closely correlated with photosynthetic area. Only one example has been found of a similar effect of family heterozygosity, namely on progeny body length in pink salmon (DUBROVA et al 1995). Maternally transmitted characters (e.g., offspring weight), however, can be particularly sensitive to inbreeding (FALCONER 1960 in Significantly positive regression coefficients were also found for day 104 at the Reykjavik site and days 41 and 104 at the Blue Lagoon site.…”

Heterozygosity–fitness correlations: new perspectives on old problems

“…In first-generation offspring of paircrosses or mass-matings, HFC due to indirect effects should be reduced or absent, as (i) all individuals tend to have similar genetic loads and (ii) inbreeding (and therefore identity desequilibrium) is generally excluded by the experimentator's control. The available evidence on noninbred laboratory strains or offspring of single pair-matings indeed shows that HFC is rare or absent under these conditions (Adamkewicz et al, 1984;Gaffney & Scott, 1984;Danzmann et al, 1988;Dubrova et al, 1995), suggesting indirect effects. However, the number of such studies with large sample sizes ( 1000) is small.…”

Study of the Genetic Adaptation Mechanisms of Siberian Larch (Larix sibirica Ledeb.) Regarding Climatic Stresses Based on Dendrogenomic Analysis

“…It is interesting to note that the confidence intervals for the correlation trends are narrower in the upper-to-middle intervals (0.14-0.15) of the heterozygosity values, and he trendlines based on the quadratic, cubic and local polynomial regression fitting better approximate the correlation between individual heterozygosity and dendrophenotypes with higher regression coefficients (Figure S1). It can be a signature of the "optimal" heterozygosity reflecting the stable individual growth and response to the stress factors and providing the maximum adaptation of an individual or a population to the environment in which the individual or population was formed and in which it now exists (in sensu [82][83][84]).…”