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Title: Why do recessive lethal alleles persist in a population over many generations? Post by: confused_student on Nov 11, 2010 Why do recessive lethal alleles persist in a population over many generations? Thank you for any help.
Title: Why do recessive lethal alleles persist in a population over many generations? Post by: bio_man on Nov 11, 2010 In a large population in which random mating occurs and in the absence of forces that change the proportions of alleles the original ratio of dominant alleles to recessive alleles will be retained from generation to generation.
Title: Why do recessive lethal alleles persist in a population over many generations? Post by: sarah! on Nov 11, 2010 Because it is recessive, individuals can be carriers of the allele without actually showing the symptoms. So it can be non-lethal to carriers (in fact, they may show no effects at all). So the allele can be passed down through generations, and hang around indefinitely in the population. Occasionally, two recessive carriers can mate and produce an offspring that gets a double-set of the allele and this will be fatal to that offspring. But in general, once the recessive allele is rare enough in the population, it's appearance becomes so infrequent that it stops getting weeded out further by natural selection, and can remain indefinitely.
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