Sickle cell disease is caused by a recessive allele. Individuals with two recessive alleles usually die of sickle cell disease before reaching reproductive age. However, individuals with only one recessive allele show few of the symptoms of the disease. The frequency of the sickle cell gene seems to be highest in populations of central Africa, a region where malaria is common. a) Do heterozygous individuals have a survival advantage over homozygous individuals in this region? Why?

Sickle cell disease is caused by a recessive allele. Individuals with two recessive alleles usually die of sickle cell disease before reaching reproductive age. However, individuals with only one recessive allele show few of the symptoms of the disease. The frequency of the sickle cell gene seems to be highest in populations of central Africa, a region where malaria is common. a) Do heterozygous individuals have a survival advantage over homozygous individuals in this region? Why?

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter21: Microevolution: Genetic Changes Within Populations

Section: Chapter Questions

Problem 12TYK: Discuss Concepts Many human diseases are caused by recessive alleles that are not expressed in...

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