EBK CONCEPTS OF GENETICS
12th Edition
ISBN: 9780134818979
Author: Killian
Publisher: YUZU
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Chapter 18, Problem 26ESP
Mutations in the low-density lipoprotein receptor (LDLR) gene are a primary cause of familial hypercholesterolemia. One such mutation is a SNP in exon 12 of the LDLR. In premenopausal women, but not in men or postmenopausal women, this SNP leads to skipping of exon 12 and production of a truncated nonfunctional protein. It is hypothesized that this SNP compromises a splice enhancer [Zhu et al. (2007). Hum Mol Genet. 16:1765–1772]. What are some possible ways in which this SNP can lead to this defect but only in premenopausal women?
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Mutations in the IL2RG gene cause approximately 30 percent of severe combined immunodeficiency disorder (SCID) cases in humans. These mutations result in alterations to a protein component of cytokine receptors that are essential for proper development of the immune system. The IL2RG gene is composed of eight exons and contains upstream and downstream sequences that are necessary for proper transcription and translation. Below are some of the mutations observed. For each, explain its likely influence on the IL2RG gene product (assume its length to be 375 amino acids). (a) Nonsense mutation in a coding region (b) Insertion in Exon 1, causing frameshift (c) Insertion in Exon 7, causing frameshift (d) Missense mutation (e) Deletion in Exon 2, causing frameshift (f) Deletion in Exon 2, in frame (g) Large deletion covering Exons 2 and 3
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Chapter 18 Solutions
EBK CONCEPTS OF GENETICS
Ch. 18 - Some mutations in the tra gene of Drosophila cause...Ch. 18 - Some scientists use the analogy that the...Ch. 18 - Consider the example that actin mRNA localization...Ch. 18 - What is alternative splicing, where does it occur,...Ch. 18 - What role might the expanded tri- and...Ch. 18 - DM1 is characterized by a phenomenon known as...Ch. 18 - HOW DO WE KNOW? In this chapter, we focused on how...Ch. 18 - CONCEPT QUESTION Review the Chapter Concepts list...Ch. 18 - List three types of alternative splicing patterns...Ch. 18 - Consider the CT/CGRP example of alternative...
Ch. 18 - Explain how the use of alternative promoters and...Ch. 18 - Explain how a tissue-specific RNA-binding protein...Ch. 18 - The regulation of mRNA decay relies heavily upon...Ch. 18 - Nonsense-mediated decay is an mRNA surveillance...Ch. 18 - AU-rich elements (AREs) are cis-elements in mRNAs...Ch. 18 - What are processing bodies (P bodies), and what...Ch. 18 - In 1998, future Nobel laureates Andrew Fire and...Ch. 18 - Present an overview of RNA interference (RNAi)....Ch. 18 - RNAi may be directed by small interfering RNAs...Ch. 18 - Prob. 14PDQCh. 18 - In principle, RNAi may be used to fight viral...Ch. 18 - Prob. 16PDQCh. 18 - Prob. 17PDQCh. 18 - Prob. 18PDQCh. 18 - Prob. 19PDQCh. 18 - How is it possible that a given mRNA in a cell is...Ch. 18 - Prob. 21PDQCh. 18 - Prob. 22PDQCh. 18 - Prob. 23PDQCh. 18 - Prob. 24ESPCh. 18 - Prob. 25ESPCh. 18 - Mutations in the low-density lipoprotein receptor...Ch. 18 - RNA helicases are a class of proteins that bind...Ch. 18 - While miRNA response elements (MREs) may be...Ch. 18 - RNAi is currently being tested as a therapeutic...Ch. 18 - The localization and translational control of...Ch. 18 - Explain how the expression of a single gene can be...
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