Genetic Analysis: An Integrated Approach (3rd Edition)
3rd Edition
ISBN: 9780134605173
Author: Mark F. Sanders, John L. Bowman
Publisher: PEARSON
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Chapter 13, Problem 17P
A hereditary disease is inherited as an autosomalrecessive trait. The wild
a. Identify the genotype of each family member, using the sizes of mRNAs to indicate each allele. (For example, a person who is homozygous wild type is indicated as
b. Based on your analysis, what is the most likely molecular abnormality causing the disease allele?
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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.
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 13 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
Ch. 13 - 13.1 Devoting a few sentences to each, describes...Ch. 13 - 13.2 Describe and give an example (real or...Ch. 13 - What is meant by the term chromatin remodeling?...Ch. 13 - 13.4 What general role does acetylation of histone...Ch. 13 - 13.5 Describe the roles of writers, readers, and...Ch. 13 - Outline the roles of RNA in eukaryotic gene...Ch. 13 - 13.7 What are the roles of the Polycomb and...Ch. 13 - Most biologists argue that the regulation of gene...Ch. 13 - Compare and contrast the transcriptional...Ch. 13 - The term heterochromatin refers to heavily...
Ch. 13 - 13.11 Compare and contrast promoters and enhancers...Ch. 13 - 13.12 What are the different chromatin...Ch. 13 - 13.13 Define epigenetics, and provide examples...Ch. 13 - What is one proposed role for lncRNAs?Ch. 13 - 13.15 What are the sources of dsRNA? Diagram the...Ch. 13 - How does dsRNA lead to posttranscriptional gene...Ch. 13 - 13.17 A hereditary disease is inherited as an...Ch. 13 - Prob. 18PCh. 13 - Prob. 19PCh. 13 - 13.20 A muscle enzyme called ME is produced by...Ch. 13 - Using the components in the accompanying diagram,...Ch. 13 - 13.22 The majority of this chapter focused on gene...
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