GENETIC ANALYSIS: AN INTEG. APP. W/MAS
2nd Edition
ISBN: 9781323142790
Author: Sanders
Publisher: Pearson Custom Publishing
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Chapter 22, Problem 19P
Sickle cell disease (SCD) is found in numerous populations whose ancestral homes are in the malaria belt of Africa and Asia. SCD is an autosomal recessive disorder that results from homozygosity for a mutant
a. What are the frequencies of the wild
b. What is the frequency of carriers of SCD in the population?
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Sickle cell anemia is caused by a recessive allele at a single gene. As we discussed in class, being a homozygote for the sickle cell allele is almost always lethal, but heterozygotes tend to be resistant against malaria although they have a mild form of anemia. Because of this heterozygote advantage, the allele for sickle cell anemia has a frequency of more than 10% in some human populations.
How would present allele frequencies of the sickle cell allele change, if there was no heterozygote advantage or disadvantage (that is, that heterozygotes would be identical to ‘normal’ homozygotes – no malaria resistance, no anemia)? How would the change in sickle cell allele frequencies compare to scenario a (extirpation of malaria)
What would happen to the frequency of heterozygous carriers of sickle-cell anemia (with AS genotype) if mosquitoes were completely wiped out in a large region?
In a randomly mating population of mice, 3 out of 200 mice are anemic. Anemia is a recessive condition where the affected mice do not have enough red blood cells to carry the required oxygen molecules to the tissues.
What is the expected frequency of the homozygous dominant genotype for anemia in this population?
Chapter 22 Solutions
GENETIC ANALYSIS: AN INTEG. APP. W/MAS
Ch. 22 - 20.1 Compare and contrast the terms in each of the...Ch. 22 - In a population, what is the consequence of...Ch. 22 - 20.3 Identify and describe the evolutionary forces...Ch. 22 - Describe how natural selection can produce...Ch. 22 - Thinking creatively about evolutionary mechanisms,...Ch. 22 - 20.6 Genetic drift, an evolutionary process...Ch. 22 - Over the course of many generations in a small...Ch. 22 - Catastrophic events such as loss of habitat,...Ch. 22 - 20.9 George Udny Yule was wrong in suggesting that...Ch. 22 - 20.10 The ability to taste the bitter compound...
Ch. 22 - Figure 20.6 illustrates the effect of an ethanol ...Ch. 22 - 20.12 Biologists have proposed that the use of...Ch. 22 - 20.13 Two populations of deer, one of them large...Ch. 22 - 20.14 Directional selection presents an apparent...Ch. 22 - 20.15 What is inbreeding depression? Why is...Ch. 22 - 20.16 Certain animal species, such as the...Ch. 22 - Genetic Analysis 20.1 predicts the number of...Ch. 22 - 20.18 In a population of rabbits, and . The...Ch. 22 - Sickle cell disease (SCD) is found in numerous...Ch. 22 - 20.20 Epidemiologic data on the population in the...Ch. 22 - The frequency of tasters and nontasters of PTC...Ch. 22 - Tay-Sachs disease is an autosomal recessive...Ch. 22 - 20.23 Cystic fibrosis (CF) is the most common...Ch. 22 - 20.24 In the mouse, Mus musculus, survival in...Ch. 22 - 20.25 In a population of flowers growing in a...Ch. 22 - Assume that the flower population described in the...Ch. 22 - 20.27 ABO blood type is examined in a Taiwanese...Ch. 22 - 20.28 A total ofmembers of a Central American...Ch. 22 - 20.29 A sample offield mice contains individuals...Ch. 22 - Prob. 30PCh. 22 - Albinism, an autosomal recessive trait...Ch. 22 - Prob. 32PCh. 22 - 20.33 Evaluate the following pedigree, and answer...Ch. 22 - Evaluate the following pedigree, and answer the...Ch. 22 - The following is a partial pedigree of the British...Ch. 22 - Draw a separate hypothetical pedigree identifying...Ch. 22 - Prob. 37PCh. 22 - 20.38 Achromatopsia is a rare autosomal recessive...Ch. 22 - 20.39 New allopolyploid plant species can arise by...
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