Essentials of Genetics, Books a la Carte Plus Mastering Genetics with eText -- Access Card Package (9th Edition)
9th Edition
ISBN: 9780134319070
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino
Publisher: PEARSON
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Chapter 14, Problem 29PDQ
Two related forms of muscular dystrophy–Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD)–are both recessive, X-linked, single-gene conditions caused by point mutations, deletions, and insertion in the dystrophin gene. Each mutated form of dystrophin is one allele. Of the two diseases, DMD is much more severe. Given your knowledge of mutations, the genetic code, and translation, propose an explanation for why the two disorders differ greatly in severity.
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Two related forms of muscular dystrophy—Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD)—are both recessive, X-linked, single-gene conditions caused by point mutations, deletions, and insertion in the dystrophin gene. Each mutated form of dystrophin is one allele. Of the two diseases, DMD is much more severe. Given your knowledge of mutations, the genetic code, and translation, propose an explanation for why the two disorders differ greatly in severity.
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.
Chapter 14 Solutions
Essentials of Genetics, Books a la Carte Plus Mastering Genetics with eText -- Access Card Package (9th Edition)
Ch. 14 - CASE STUDY| Genetic dwarfism Seven months...Ch. 14 -
CASE STUDY | Genetic dwarfism
Seven months...Ch. 14 -
CASE STUDY| Genetic dwarfism
Seven months...Ch. 14 - CASE STUDY | Genetic dwarfism Seven months...Ch. 14 -
HOW DO WE KNOW?
1. In this chapter, we focused on...Ch. 14 - Review the Chapter Concepts list on page 257....Ch. 14 - What is a spontaneous mutation, and why are...Ch. 14 -
4. Why would a mutation in a somatic cell of a...Ch. 14 - Why is a random mutation more likely to be...Ch. 14 - Most mutations in a diploid organism are...
Ch. 14 - What is meant by a conditional mutation?Ch. 14 -
8. Describe a tautomeric shift and how it may...Ch. 14 - Contrast and compare the mutagenic effects of...Ch. 14 - Why are frameshift mutations likely to be more...Ch. 14 - Why are X rays more potent mutagens than UV...Ch. 14 -
12. DNA damage brought on by a variety of natural...Ch. 14 - Contrast the various types of DNA repair...Ch. 14 -
14. Mammography is an accurate screening...Ch. 14 - Describe how the Ames test screens for potential...Ch. 14 - What genetic defects result in the disorder...Ch. 14 - In a bacterial culture in which all cells are...Ch. 14 - Human equivalents of bacterial DNA mismatch repair...Ch. 14 - A number of different types of mutations in the...Ch. 14 -
20. Some mutations that lead to diseases such as...Ch. 14 - In maize, a Ds or Ac transposon can cause...Ch. 14 -
22. Presented here are hypothetical findings from...Ch. 14 -
23. Cystic fibrosis (CF) is a severe autosomal...Ch. 14 -
24. Electrophilic oxidants are known to create...Ch. 14 - Skin cancer carries a lifetime risk nearly equal...Ch. 14 -
26. The initial discovery of IS elements in...Ch. 14 -
27. It is estimated that about 0.2 percent of...Ch. 14 -
28. It has been noted that most transposons in...Ch. 14 - Two related forms of muscular dystrophy–Duchenne...
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