  Transgenerational inheritance of a trait is presumably affected by both
genetic and environmental factors but remains poorly understood. We studied the
effect of genetic polymorphisms on transgenerational inheritance of yeast
segregants that were derived from a cross between a laboratory strain and a
wild strain of Saccharomyces cerevisiae. For each SNP analyzed, the parental
allele present in less than half of the segregants panel was called the minor
allele (MA). We found a nonrandom distribution of MAs in the segregants,
indicating natural selection. We compared segregants with high MA content (MAC)
relative to those with less and found a more dramatic shortening of the lag
phase length for the high MAC group in response to 14 days of ethanol training.
Also, the short lag phase as acquired and epigenetically memorized by ethanol
training was more dramatically lost after 7 days of recovery in ethanol free
medium for the high MAC group. Sodium chloride treatment produced similar
observations. Using public datasets, we found MAC linkage to mRNA expression of
hundreds of genes. Finally, we found preferential effect of MAC on traits with
high number of known additive quantitative trait loci (QTLs). These results
provide evidence for the slightly deleterious nature of most MAs and a lower
capacity to maintain inheritance of traits in individuals or cells with greater
MAC, which have implications for disease prevention and treatment and the
"missing heritability" problem in complex traits and diseases.
