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 12CONQ
Achondroplasia is a rare form of dwarfism caused by an autosomal dominant mutation that affects the gene that encodes a fibroblast growth factor receptor. Among 1,422,000 live births, the number of babies born with achondroplasia was 31. Among those 31 babies, 18 of them had one parent with achondroplasia. The remaining babies had two unaffected parents. How do you explain those 13 babies, assuming that the mutant allele has 100% penetrance? What are the odds that these 13 individuals will pass this mutant gene to their offspring?
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Achondroplasia is an autosomal dominant disorder characterized by disproportionate short stature: the legs and arms of people with achondroplasia are short compared with the head and trunk. The disorder is due to a base substitution in the gene, located on the short arm of chromosome 4, that encodes fibroblast growth factor receptor 3 (FGFR3). Although achondroplasia is clearly inherited as an autosomal dominant trait, more than 80% of the people who have achondroplasia are born to parents with normal stature. This high percentage indicates that most cases are caused by newly arising mutations; these cases (not inherited from an affected parent) are referred to as sporadic. Studies have demonstrated that sporadic cases of achondroplasia are almost always caused by mutations inherited from the father (paternal mutations). In addition, the occurrence of achondroplasia is higher among the children of older fathers; approximately 50% of children with achondroplasia are born to fathers…
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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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