Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 21, Problem 9P
Alkaptonuria is a recessive autosomal genetic disorder associated with darkening of the urine. In the United States, approximately 1 out of every 250,000 people has alkaptonuria.
a. | Assuming Hardy-Weinberg equilibrium, estimate the frequency of the allele responsible for this trait. |
b. | What proportion of people in the U.S. population are carriers for this trait? In this population, what is the ratio of carriers to individuals affected by alkaptonuria? |
c. | If a woman without alkaptonuria had a child with this trait with one husband then remarried, what is the chance that a child produced by her second marriage would have alkaptonuria? |
d. | Alkaptonuria is a relatively benign condition, so there is little selective advantage to individuals with any genotype; as a result, your assumption of Hardy-Weinberg equilibrium in part (a) is reasonable. Could you also use the assumption of Hardy-Weinberg equilibrium to estimate the allele frequencies and carrier frequencies of more severe recessive autosomal conditions such as cystic fibrosis? Explain. |
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Chapter 21 Solutions
Genetics: From Genes to Genomes
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