Genetics: From Genes to Genomes, 5th edition
5th Edition
ISBN: 9780073525310
Author: Leland H. Hartwell, Michael L. Goldberg, Janice A. Fischer, Leroy Hood, Charles F. Aquadro
Publisher: McGraw-Hill Education
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Chapter 20, Problem 17P
Androgenetic alopecia (pattern baldness) is a complex trait in humans governed by several genes, but suppose a human population exists in which a single autosomal allele determines pattern baldness. This allele is dominant in males and recessive in females. The population is in Hardy-Weinberg equilibrium, and 51% of the men are bald.
| a. | What is the allele frequency of the baldness allele among males? |
| b. | What is the allele frequency of the baldness allele among females? |
| c. | What percentage of the women in this population will exhibit pattern baldness? |
| d. | Assuming random mating, what proportion of all matings should be between a bald man and a nonbald woman? |
| e. | What percentage of the bald men in the population are heterozygotes? |
| f. | If a nonbald couple produces a bald son, what is the probability that their next son will be bald? |
| g. | A woman with androgenetic alopecia has a daughter, but nothing is known about the father. What is the probability that the daughter will be bald? |
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Androgenetic alopecia (pattern baldness) is a complextrait in humans governed by several genes, but supposea human population exists in which a single autosomalallele determines pattern baldness. This allele is dominant in males and recessive in females. The population is in Hardy-Weinberg equilibrium, and 51% ofthe men are bald.a. What is the allele frequency of the baldness alleleamong males?b. What is the allele frequency of the baldness alleleamong females?c. What percentage of the women in this populationwill exhibit pattern baldness? d. Assuming random mating, what proportion of allmatings should be between a bald man and anonbald woman?e. What percentage of the bald men in the populationare heterozygotes?f. If a nonbald couple produces a bald son, what isthe probability that their next son will be bald?g. A woman with androgenetic alopecia has a daughter, but nothing is known about the father. What isthe probability that the daughter will be bald?
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Chapter 20 Solutions
Genetics: From Genes to Genomes, 5th edition
Ch. 20 - Choose the best matching phrase in the right...Ch. 20 - When an allele is dominant, why does it not always...Ch. 20 - A population with an allele frequency p of 0.5 and...Ch. 20 - Prob. 4PCh. 20 - Which of the following populations are at...Ch. 20 - A dominant mutation in Drosophila called Delta...Ch. 20 - A large, random mating population is started with...Ch. 20 - Prob. 8PCh. 20 - Prob. 9PCh. 20 - Two hypothetical lizard populations found on...
Ch. 20 - It is the year 1998, and the men and women sailors...Ch. 20 - Prob. 12PCh. 20 - In 1927, the ophthalmologist George Waaler tested...Ch. 20 - Prob. 14PCh. 20 - A gene has two alleles A frequency = p and a...Ch. 20 - Some people can taste the bitter compound...Ch. 20 - Androgenetic alopecia pattern baldness is a...Ch. 20 - Why is the elimination of a fully recessive...Ch. 20 - Tristan da Cunha is a group of small islands in...Ch. 20 - Small population size causes genetic drift because...Ch. 20 - Prob. 21PCh. 20 - A mouse mutation with incomplete dominance t =...Ch. 20 - In Drosophila, the vestigial wings recessive...Ch. 20 - Prob. 24PCh. 20 - You have identified an autosomal gene that...Ch. 20 - In Europe, the frequency of the CF allele causing...Ch. 20 - An allele of the G6PD gene acts in a recessive...Ch. 20 - Explain why evolutionary biologists monitor...Ch. 20 - What is the most straightforward evidence at the...Ch. 20 - In March 2013, the American Journal of Human...Ch. 20 - If you go back 40 generations into your biological...Ch. 20 - In Fig. 21.17, to what part of the world does...Ch. 20 - Predict the DNA sequences at the four nodes...Ch. 20 - A cladogram not drawn to scale for the taxonomic...Ch. 20 - As noted in Fig. 21.22, humans now living in...
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