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
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 20, Problem 19P
Tristan da Cunha is a group of small islands in the middle of the Atlantic Ocean. In 1814, a group of 15 British colonists founded a settlement on these islands. In 1885, 15 of the 19 males on the island were lost in a shipwreck. In the late 1960s, four cases of retinitis pigmentosa, which progressively leads to blindness, were found among the 240 descendants of these settlers remaining on the island. The frequency of retinitis pigmentosa in Britain is about 1 in 6000. Explain the high incidence of this disease on Tristan da Cunha relative to that seen in Britain.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
What impact might a vaccine against malaria have on the frequency of the Sickle Cell allele in Africa in the long run?
About 9 percent of Caucasian males are color-blind andcannot distinguish red-colored from green-coloredobjects.a. Offer one genetic model for color blindness.b. Explain why and how color blindness has reached afrequency of 9 percent in this population
It is the year 1998, and the men and women sailors (in
equal numbers) on the American ship the Medischol
Bounty have mutinied in the South Pacific and settled
on the island of Bali Hai, where they have come into
contact with the local Polynesian population. Of the
400 sailors that come ashore on the island, 324 have
MM blood type, 4 have the NN blood type, and 72 have
the MN blood type. Already on the island are 600 Poly-
nesians between the ages of 19 and 23. In the Polyne-
sian population, the allele frequency of the M allele is
0.06, and the allele frequency of the Nallele is 0.94. No
other people come to the island over the next 10 years.
a. What is the allele frequency of the N allele in the
sailor population that mutinied?
b. It is the year 2008, and 1000 children have been born
on the island of Bali Hai. If the mixed population of
1000 young people on the island in 1998 mated ran-
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...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- It is the year 1998, and the men and women sailors (in equal numbers) on the American ship the Medischol Bounty have mutinied in the South Pacific and settled on the island of Bali Hai, where they have come into contact with the local Polynesian population. Of the 400 sailors that come ashore on the island, 324 have MM blood type, 4 have the NN blood type, and 72 have the MN blood type. Already on the island are 600 Poly- nesians between the ages of 19 and 23. In the Polyne- sian population, the allele frequency of the M allele is 0.06, and the allele frequency of the N allele is 0.94. No other people come to the island over the next 10 years. a. What is the allele frequency of the N allele in the sailor population that mutinied?arrow_forwardA condition known as icthyosis hystrix gravior appeared in a boy in the early eighteenth century. His skin became very thick and formed loose spines that were sloughed off at intervals. When he grew up, this “porcupine man” married and had six sons, all of whom had this condition, and several daughters, all of whom were normal. For four generations, this condition was passed from father to son. From this evidence, what can you postulate about the location of the gene?arrow_forwardExplain the High frequency of the sickle-cell allele HbβS in regions of Africa where malaria is prevalent?arrow_forward
- In parts of equatorial Africa, where the malaria parasite is most common, the sickle-cell allele constitutes 20% of the ß-hemoglobin alleles in the human gene pool. The sickle cell trait provides an advantage against malaria compared to people with normal hemoglobin. In the United States, the parasite that causes malaria is not present, but African Americans whose ancestors were from equatorial Africa have the sickle-cell B- hemoglobin allele. These differences in traits illustrate O inclusive fitness because people have evolved molecular differences to adapt to environmental stimuli O inclusive fitness because ß-hemoglobin increases the proliferation of beneficial traits in the population O relative fitness because people have evolved molecular differences to an environmental pathogen O relative fitness because the molecular differences in ß-hemoglobin are passed to the next generationarrow_forwardAbout 4 percent of people of Northern European descent have a cystic fibrosis allele, but only about 1 in 2,500 of these people actually has the disorder. What is the most likely reason for this finding?arrow_forwardIf, within specific regional populations over two thousand years ago, sickle-cell anemia killed those individuals born with it before they could reproduce to pass it on to offspring, how did it persist in these populations? Group of answer choices A-Because of late-onset of the disease. B-Because it is cause by a virus and it spreads faster than people died. C-Because of the basic principles of mendelian inheritance that result in some heterozygote "carrier" combinations. D-Because malaria made it possible to survive sickle cell anemia since the parasite would carry oxygen on the blood cells with the mutated hemoglobin. E-It does not persist. Natural selection removes the allele because people die from both malaria and sickle-cell anemia.arrow_forward
- Familial Mediterranean fever is an inheritable disorder that causes inflammation in the abdomen, chest, or joints. Let F be the dominant allele and let f be the recessive allele. The genotypes of individuals II-4, III-2, and IV-3, respectively, are Select one: a. F_, F_, and F_ b. F_, FF, and Ff c. Ff, F_, and Ff d. F_, Ff, and F_arrow_forwardSuppose we define the Alzheimer’s disease phenotype as being diagnosed with the disease by age 75 years. In the human population, there are three alleles of the ApoE gene: ε2, ε3, ε4. They form an allelic series such that: 70% of 75 year olds with the ε4/ ε4 genotype have the Alzheimer’s phenotype 60% of 75 year olds with the ε3/ ε4 genotype have the Alzheimer’s phenotype 40% of 75 year olds with the ε3/ ε3 genotype have the Alzheimer’s phenotype 30% of 75 year olds with the ε2/ ε4 genotype have the Alzheimer’s phenotype 10% of 75 year olds with the ε2/ ε3 genotype have the Alzheimer’s phenotype If I have the ε4/ ε4 genotype and my wife has the ε2/ ε3 genotype, what is the probability that our child will have Alzheimer’s by age 75. Explain your reasoningarrow_forwardSuppose we define the Alzheimer’s disease phenotype as being diagnosed with the disease by age 75 years. In the human population, there are three alleles of the ApoE gene: ε2, ε3, ε4. They form an allelic series such that: 70% of 75 year olds with the ε4/ ε4 genotype have the Alzheimer’s phenotype 60% of 75 year olds with the ε3/ ε4 genotype have the Alzheimer’s phenotype 40% of 75 year olds with the ε3/ ε3 genotype have the Alzheimer’s phenotype 30% of 75 year olds with the ε2/ ε4 genotype have the Alzheimer’s phenotype 10% of 75 year olds with the ε2/ ε3 genotype have the Alzheimer’s phenotype If I have the ε4/ ε4 genotype and my wife has the ε2/ ε3 genotype, what is the probability that our child will have Alzheimer’s by age 75. Explain your reasoning. [Can be answered in less than 75 words]arrow_forward
- If 9% of an African population is born with a severe form of sickle-cell anemia (ss), what percentage of the population will be more resistant to malaria because they are heterozygous (Ss) for the sickle-cell gene?arrow_forwardSickle cell anemia is a genetically inherited autosomal recessive trait in which results in a condition that there are not enough healthy red blood cells to carry oxygen throughout the body due to the production of red blood cells that are sickle shaped. The frequency of the sickle cell condition is as high as 10% in Central Africa compared to 0.5% in the United States. Malaria is a disease caused by a parasite that infects healthy red blood cells and can lead to death. However, the parasite is not able to infect sickle cell red blood cells. Scientists claim that the higher frequency of sickle cell carriers is due to the presence of malaria. Provide reasoning to support the claim.arrow_forwardHumans who are born homozygous for the recessive sickle cell allele die of sickle cell anemia, while those who are heterozygous are resistant to malaria. 5% of the population of the Congo are homozygous recessive for the sickle cell allele. What percentage of the population is resistant to malaria?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage Learning
Human Biology (MindTap Course List)
Biology
ISBN:9781305112100
Author:Cecie Starr, Beverly McMillan
Publisher:Cengage Learning
TISSUE REPAIR Part 1: Repair - Regeneration; Author: ilovepathology;https://www.youtube.com/watch?v=t-5EjlS6qjk;License: Standard YouTube License, CC-BY