Words similar to overdominance
Example sentences for: overdominance
How can you use “overdominance” in a sentence? Here are some example sentences to help you improve your vocabulary:
In this situation, population heterozygote advantage does not require overdominance, but merely allele effects that are more than additive (partial dominance).
As we have suggested above, it is biologically and epidemiologically useful to determine (a) the beneficial or harmful effects of specific alleles, and (b) the effects of heterozygosity, such as allele-specific overdominance; we show here that unconditional comparisons of all heterozygotes to all homozygotes can reflect either or both of these, and cannot distinguish them.
Our results do not deny that allele-specific overdominance at HLA exists in human populations with respect to infectious disease resistance, but simply raise doubts about the reliability of the major evidence that has been adduced in support of this phenomenon.
Moreover, direct estimates of the allele-specific effects of heterozygosity (relative to the corresponding homozygotes), nearly absent in the infectious disease-HLA literature, are frequently found in studies of HLA genotype and chronic (mostly autoimmune) diseases [ 28 29 30 ] . We do not know the reason for this difference in approach, but suspect that some infectious disease investigators, informed by the evolutionary hypothesis of overdominance for infectious disease resistance and by animal studies, may have a special interest in detecting effects of heterozygosity per se . Many studies of HLA-autoimmune disease associations, on the other hand, seem to focus more on the effects of individual alleles and, having established these, move on to investigate the dependence of these effects on genetic modifiers, including the identity of the individual's other allele at the same locus.
We have shown that when allele-specific overdominance exists, it will often be manifest as population heterozygote advantage, but that a finding of population heterozygote advantage may be consistent with other patterns of allele-specific effects; for example, when resistant and susceptible alleles are equally common and equally diverse, population heterozygote advantage will occur if allele-specific effects are additive, dominant or overdominant.
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