Some genetic disorders are caused by autosomal recessive alleles. Many such alleles are recessive lethals, causing lethality very early in life (say, before the age of 20 yrs). Intuitively one might suggest that selection working on human population should completely remove such alleles from the population. Yet, there are many examples of such lethal genetic disorders occurring in low frequency in several human populations. Why is it almost impossible to completely remove these seemingly fitness-detrimental alleles from the population? Under what condition, extinction of such an allele from a population can be achieved?

Some genetic disorders are caused by autosomal recessive alleles. Many such alleles are recessive lethals, causing lethality very early in life (say, before the age of 20 yrs). Intuitively one might suggest that selection working on human population should completely remove such alleles from the population. Yet, there are many examples of such lethal genetic disorders occurring in low frequency in several human populations. Why is it almost impossible to completely remove these seemingly fitness-detrimental alleles from the population? Under what condition, extinction of such an allele from a population can be achieved?

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Description: Some genetic disorders are caused by autosomal recessive alleles. Many such alleles are recessive lethals, causing lethality very early in life (say, before the age of 20 yrs). Intuitively one might suggest that selection working on human population

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter10: From Proteins To Phenotypes

Section: Chapter Questions

Problem 23QP

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