Genetic diversity is a measure of the total number of alleles within a population, and it is mutation, the ultimate source of all genetic variation, that gives rise to new alleles. Favorable mutations are rare and are greatly outnumbered by mutations that are selectively neutral or deleterious (that is, lethal or sublethal). In diploid organisms, most deleterious mutant alleles are hidden from view because they are typically (but not always) recessive and are masked by a second, normal or... więcej

Salem Press Encyclopedia of Health, 2023. 3p.