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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Duchenne muscular dystrophy (DMD) is an X-linked recessive genetic disease caused by mutations in the gene that encodes dystrophin, a large protein that plays an important role in the development of normal muscle fibers. The Dystrophin gene is immense, spanning 2.5 million base pairs, and includes 79 exons and 78 introns. Many of the mutations that cause DMD produce premature stop codons, which bring protein synthesis to a halt, resulting in a greatly shortened and nonfunctional form of dystrophin.
Some geneticists have proposed treating DMD patients by introducing small RNA molecules that cause the spliceosome to skip the exon containing the stop codon (A. Goyenvalle et al., 2004. Science 306:1796–1799). The introduction of the small RNAs will produce a protein that is somewhat shortened because an exon is skipped and some amino acids are missing, but it may still result in a protein that has some function.
The small RNAs, antisense RNAs, used for exon skipping are complementary to…
Duchenne muscular dystrophy (DMD) is an X-linked recessive genetic disease caused by mutations in the gene that encodes dystrophin, a large protein that plays an important role in the development of normal muscle fibers. The dystrophin gene is immense, spanning 2.5 million base pairs, and includes 79 exons and 78 introns. Many of the mutations that cause DMD produce premature stop codons, which bring protein synthesis to a halt, resulting in a greatly shortened and nonfunctionalform of dystrophin. Some geneticists have proposed treating DMD patients by causing the spliceosome to skip the exon containing the stop codon. Exon skipping would produce a protein that is somewhat shortened (because an exon is skipped and some amino acids are missing), but might still result in a protein that had some function (A. Goyenvalle et al. 2004. Science 306:1796–1799). Propose a possible mechanism to bring about exon skipping for the treatment of DMD.
Achondroplasia is a form of dwarfism in humans. It is caused by a mutant allele of the fibroblast growth factor receptor 3 gene ( FGFR3) that produces an overactive protein. Having one copy of the mutant allele results in dwarfism. Two copies of the mutant allele results in death before birth.
If a man with Achondroplasia marries a woman who is Sickle Cell Anemia carrier and they have a child together, what is the probability that their child will Achondroplasia AND be a Sickle Cell Anemia carrier?
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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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