Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Chapter 25, Problem 14CONQ
Marfan syndrome is due to a mutation in a gene that encodes a protein called fibrillin-1. It is inherited as a dominant trait. The fibrillin-1 protein is the main constituent of extracellular microfibrils. These microfibrils can exist as individual fibers or associate with a protein called elastin to form elastic fibers. People with the disorder tend to be unusually tall with long limbs, and they may have defects in their heart valves and aorta. Let’s suppose a
A. What is the probability this child will have the disease?
B. If this couple has three children, what is the probability that none of them will have Marfan syndrome?
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Sickle-cell disease (often called sickle-cell anemia) is a disease that is caused by a mutation to the gene that is responsible for producing the protein hemoglobin. Remember that hemoglobin is a protein in the red blood cells which is responsible for carrying oxygen throughout the body. When a person possesses the mutated hemoglobin allele, their red blood cells take on an altered shape and this results in a variety of symptoms ranging from general weakening of the body, damage to the organs and even death. The sickle cell allele is recessive to the healthy allele, thus only individuals that are homozygous for the recessive allele will have sickle-cell disease. Individuals that are homozygous for the healthy allele, along with heterozygous, individuals will be physically healthy.
Question:
Given that this mutated allele will cause disease and death in individuals, what would you predict to occur to the frequency of this allele in the population? Explain.
Huntington disease (HD) is an inherited neurodegenerative disorder characterized by gradual, irreversible impairment of psychological, motor, and cognitive functions. Symptoms typically appear in middle age, but onset can occur at almost any age, and the course of the disease can range from 15 to 20 years. The molecular basis of HD is becoming better understood, and the genetic mutation has been traced to a gene that encodes a large protein of unknown function. In individuals who will not develop HD, a region of the gene that encodes the N-terminus of this protein has a sequence of CAG codons (for glutamine) repeated 6 to 39 times in succession.
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In those with childhood-onset HD, it is repeated more than 70 times.
*codon: refers to the 3 nucleotides that code for amino acid.
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Sandhoff disease is due to a mutation in a gene that encodes a proteincalled hexosaminidase B. This disease has symptoms that aresimilar to those of Tay-Sachs disease. Weakness begins in the first 6 months of life. Individuals exhibit early blindness and progressive mental and motor deterioration. The family in the pedigree shown below has three members with Sandhoff disease, indicated with black symbols.
Chapter 25 Solutions
Genetics: Analysis and Principles
Ch. 25.1 - Which of the following wouldnotbe consistent with...Ch. 25.1 - 2. Assuming complete penetrance, which type of...Ch. 25.1 - 3. Which of the following is not a common...Ch. 25.1 - Prob. 4COMQCh. 25.2 - Prob. 1COMQCh. 25.2 - Haplotype association studies are aimed at the...Ch. 25.3 - 1. Which of the following is not a method used in...Ch. 25.3 - 2. Which of the following prenatal genetic testing...Ch. 25.4 - Prob. 1COMQCh. 25.5 - 1. An oncogene is produced from a ________that has...
Ch. 25.5 - Which of the following is a type of genetic change...Ch. 25.5 - 3. Tumor-suppressor genes promote cancer...Ch. 25.5 - 4. Normal (nonmutant) tumor-suppressor genes often...Ch. 25.5 - Prob. 5COMQCh. 25.6 - Prob. 1COMQCh. 25 - 1. With regard to pedigree analysis, make a list...Ch. 25 - 2. Explain, at the molecular level, why human...Ch. 25 - 3. Many genetic disorders exhibit locus...Ch. 25 - Prob. 4CONQCh. 25 - Prob. 5CONQCh. 25 - Figure 25.1 illustrates albinism in two different...Ch. 25 - Prob. 7CONQCh. 25 - Prob. 8CONQCh. 25 - Ehler-Danlos syndrome is a rare disorder caused by...Ch. 25 - 10. Hurler syndrome is due to a mutation in a gene...Ch. 25 - Like Hurler syndrome, Fabry disease involves an...Ch. 25 - Achondroplasia is a rare form of dwarfism caused...Ch. 25 - Prob. 13CONQCh. 25 - 14. Marfan syndrome is due to a mutation in a...Ch. 25 - 15. Sandhoff disease is due to a mutation in a...Ch. 25 - Describe the two assumptions that underlie the...Ch. 25 - Prob. 17CONQCh. 25 - What is a prion? Explain how a prion relies on...Ch. 25 - 19. Some people have a genetic predisposition for...Ch. 25 - What is the difference between an oncogene and a...Ch. 25 - Prob. 21CONQCh. 25 - Prob. 22CONQCh. 25 - Prob. 23CONQCh. 25 - Prob. 24CONQCh. 25 - Prob. 25CONQCh. 25 - Prob. 26CONQCh. 25 - Prob. 27CONQCh. 25 - With regard to cancer cells, which of the...Ch. 25 - Prob. 29CONQCh. 25 - 1. Which of the following experimental...Ch. 25 - Prob. 2EQCh. 25 - 3. What is meant by the term genetic testing? How...Ch. 25 - Prob. 4EQCh. 25 - 5. Chapter 21 describes a method known as Western...Ch. 25 - 6. An experimental assay for the blood-clotting...Ch. 25 - 7. Discuss ways to distinguish whether a...Ch. 25 - 8. The codon change (Gly-12 to Val-12) in...Ch. 25 - Explain how DNA microarrays are used in molecular...Ch. 25 - Make a list of the benefits that may arise from...Ch. 25 - 2. Our government has finite funds to devote to...Ch. 25 - Prob. 3QSDC
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