Tay-Sachs is inherited as an autosomal recessive allele. Homozygous individuals die within the first few years of life. However, there is some evidence that heterozygous individuals are more resistant to tuberculosis. Which of the following statements
about Tay-Sachs is true?
A) The allele for Tay-Sachs is always selected against.
B) This situation is an example of heterozygote advantage if tuberculosis is present in a population.
C) This situation is an example of disruptive selection.
D) Heterozygotes will be more fit than either homozygote regardless of environmental conditions.
Answer: B
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