Olsen said favored gene variants (alleles) that are relatively insensitive to background effects and highly responsive to selection.
But finding these alleles in the first place must have said difficult Olsen. Only a subset of the genes in the wild population would have produced reliably a favored trait regardless of the crop variety into
In this as in other epistatic interactions the effect of an allele at one location depends on the state of the allele at the other location.
Shattering in plants with a wild green-millet allele at the QTLI location depends on the allele at the QTL2 location.
In contrast shattering in plants with the foxtail-millet allele at QTL1 is unaffected by the allele at the QTL2 location.
In the limited number of examples at their disposal the scientists found it to be generally true that that domesticated alleles were less sensitive to genetic background than wild alleles.
plants with the domesticated tb1 gene allele are unbranched whether or not they are crowded. Unlike companion-animal breeders early farmers seem to have selected domestication-gene alleles that are insensitive to genetic background and to the environment.
This process would have been slow unrewarding and difficult to understand because the effects of gene variants on the plant weren't stable.
But once sensitive alleles had been replaced with robust ones breeders would have been able to exert strong selection pressure on plant traits shaping them much more easily than before
but because almost every female is a heterozygote (possesses a resistant and susceptible allele) it did not seem this could cause any variation in resistance.
However from application of a newly-developed qpcr diagnostic it was found that the ACE-1 gene was duplicated in some individuals with those resistant to carbamate much more likely to have duplicated additional copies of the resistant ACE-1 allele.
They contain two copies of each chromosome. Male honey bees known as drones on the other hand are haploid
and contain only one chromosome set. The haploid susceptibility hypothesis predicts that haploid males are more prone to disease compared to their diploid female counterparts
because dominant genes on one chromosome copy have the op-portunity to mask mutated genes on the other copy in diploid organisms.
TUM researchers have discovered now that a mutation in the TMEM95 gene on cattle chromosome 19 makes bulls effectively infertile with a success rate for insemination of less than 2 percent.
This is at least the seventh example in livestock of an allele that is deleterious in the homozygous state being maintained at high frequency in the populations because of the selective advantage it confers to heterozygotes.
an abnormality in the chromosomes that stop female fish from reproducing. plans to sterilize embryos in Canada before shipping them to Panama,
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