Essentials of Genetics (9th Edition) - Standalone book
9th Edition
ISBN: 9780134047799
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 19, Problem 14PDQ
Summary Introduction
To review:
The effect of gene therapy techniques on the loss-of-function mutation and gain-of-function mutation.
Introduction:
Gene therapy is a newly emerging technique in the field of
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Explain why loss-of-function mutations are frequently recessive, whereas gain-of-function mutations are frequently dominant.
Leber congenital amaurosis (LCA) is a form of congenital blindness in humans and is known to be caused by homozygosity for recessive mutations in the RPE65 gene. Recently, a rare dominant mutation in RPE65 has been implicated as one cause of an eye disease called retinitis pigmentosa, which is characterized by retinal degeneration that can progress to blindness. The dominant RPE65 mutation is a missense mutation causing amino acid 447 in the polypeptide to change from Asp to Glu. Little is known about the nature of the mutant protein.
a. Do you think that the dominant allele is more likely a loss-of-function or a gain-of-function mutation? Explain.
b. Recently a group of clinicians and scientists reported that gene therapy (gene replacement therapy) for LCA has been at least partially successful. Do you think that the same kind of gene therapy can be used for patients with retinitis pigmentosa caused by the dominant mutant allele of RPE65? Explain.
Gene mutations can be classified in two major ways:(1) hereditary or germline mutations that are inherited from a parent and are present throughout a person’s life in virtually every cell in the body.(2) acquired or somatic mutations that occur at some time during a person’s life and are present only in certain cells, not in every cell in the body.If there is no family history of a particular disease but a child has the disease then it may have arisen due to a(n) ________ mutation early during development.
A) acquired
B) inherited
C) silent
D) transition
Chapter 19 Solutions
Essentials of Genetics (9th Edition) - Standalone book
Ch. 19 - CASE STUDY| Cancer-killing bacteria Ralph, a...Ch. 19 - CASE STUDY| Cancer-killing bacteria Ralph, a...Ch. 19 - CASE STUDY |Cancer-killing bacteria Ralph, a...Ch. 19 - HOW DO WE KNOW? In this chapter, we focused on a...Ch. 19 - Prob. 2PDQCh. 19 - Why are most recombinant human proteins produced...Ch. 19 - Prob. 4PDQCh. 19 - One of the major causes of sickness, death, and...Ch. 19 - Prob. 6PDQCh. 19 - Sequencing the human genome and the development of...
Ch. 19 - Prob. 8PDQCh. 19 - As genetic testing becomes widespread, medical...Ch. 19 - What limits the use of differences in restriction...Ch. 19 - Might it make sense someday to sequence every...Ch. 19 - What is the main purpose of genome-wide...Ch. 19 - Prob. 13PDQCh. 19 - Prob. 14PDQCh. 19 -
15. In 2013 the actress Angelina Jolie elected to...Ch. 19 - Prob. 16PDQCh. 19 - Should the FDA regulate direct-to-consumer genetic...Ch. 19 - Prob. 18PDQCh. 19 - Prob. 19PDQCh. 19 - Private companies are now offering personal DNA...Ch. 19 - Yeager, M., et al.(Nature Genetics 39: 645–649,...Ch. 19 - In March 2010 Judge R. Sweet ruled to invalidate...
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
- Name three different types of loss of function mutations and in each case explain how the mutation exerts a loss of function effect on a genearrow_forwardLeber Congenital Amaurosis (LCA) causes progressive vision loss due to defects in the gene that encodes RPE65 isomerase. Affected individuals are homozygous recessive for mutant alleles of the RPE65 gene. You are trying to determine the molecular nature of the mutations in three individuals with LCA. For ease of analysis, you may assume that each individual is homozygous for the same mutant allele (though the three individuals have different mutations than each other). You use the polymerase chain reaction to amplify DNA from each patient and you determine the sequence of the DNA and compare it to unaffected individuals. You identify the following differences. Note that the non-template strand of DNA is given and the changes are highlighted using red boldface. You can assume that the sequences are in the first reading frame (eg. the first three nucleotides of each sequence is a codon). The coding region of the gene is 1602 bp and the position of the sequences shown below is…arrow_forwardDuchenne Muscular Dystrophy (DMD) is a disorder that primarily affects the function of skeletal muscles used for movement and cardiac muscles used for heart beating. Dystrophin is a protein encoded by a single gene, DMD, that is expressed in skeletal and cardiac muscle. Some forms of muscular dystrophy may be caused by different mutations in the DNA sequence of the DMD gene. Because the DMD locus is on the X chromosome, males are affected at higher rates. Two brothers, one of whom has DMD and one of whom does not, worked with their genetic counselor (Links to an external site.) to have their DMD gene sequenced to identify genetic variation that may explain why one brother was affected and the other not. Because DMD is a very long gene, a fictionalized, simplified model of the results is presented here (Figure 1). The actual DMD mRNA is about 16,000 base-pairs!------Consider single nucleotide polymorphism (SNP) #1 (Figure 1). Is this mutation likely to cause Duchenne muscular…arrow_forward
- Explain the difference between a gain-of-function mutation and a dominant-negative mutation.arrow_forwardTwo major categories of mutations are germline mutations and somatic mutations. Select one: True Falsearrow_forwardBRCA1 is mutated in a large percentage of hereditary breast and ovarian cancers. BRCA1 protein serves as a key enzyme in repairing DNA double-strand breaks. More than 800 mutations in the BRCA1 are clinically significant. This collection of mutations include missense mutations, small deletions, and large rearrangements that result in a protein with reduced function or no protein product. BRCA1 functions by interacting with a variety of proteins, such as Rb, Myc, cyclin-dependent kinase (CDK), and Rad50/51. Rb is important for cell cycle arrest; Myc is a transcription factor that activates genes required for cell proliferation; activated CDK promotes cell cycle progression; and Rad50/51 proteins facilitate repair of DNA double-strand breaks. How many of the mutations listed below would lead to excessive cell growth when the cell was either homozygous or heterozygous for the mutation? Increased expression of Myc Constitutively active Rad50/51 A null mutation in Rb Continuous production…arrow_forward
- Discuss the consequences of a germ-line versus a somatic mutation.arrow_forwardResearchers have identified a gene in humans that (when mutated) causes tremors and unstable walking due to neurological problems. This disorder is inherited in an autosomal recessive manner, and the mutant allele isknown to result from a loss-of-function mutation. The same gene hasbeen found in mice, although a mutant mouse version has not beendiscovered. To develop an effective drug therapy to treat this disorderin humans, it would be experimentally useful to have a mouse model.In other words, it would be desirable to develop a strain of mice thatcarry the mutant allele in the homozygous condition. How would youdevelop such a strain?arrow_forwardHuntington disease (HD) is an inherited neurodegenerative disorder characterized by gradual, irreversible impairment of psychological, motor, and cognitive functions. Symptoms typically appear in middle age, but onset can occur at almost any age, and the course of the disease can range from 15 to 20 years. The molecular basis of HD is becoming better understood, and the genetic mutation has been traced to a gene that encodes a large protein of unknown function. In individuals who will not develop HD, a region of the gene that encodes the N-terminus of this protein has a sequence of CAG codons (for glutamine) repeated 6 to 39 times in succession. In individuals with adult-onset HD, this codon (3 nucleotides) is typically repeated 40 to 55 times In those with childhood-onset HD, it is repeated more than 70 times. *codon: refers to the 3 nucleotides that code for amino acid. A small portion of the coding sequence of the HD gene is given below. The nucleotide sequence of the DNA is…arrow_forward
- MSH2 is a gene commonly associated with HNPCC (Hereditary nonpolyposis colorectal cancer). This gene encodes a protein that is involved in mismatch repair. Why are individuals who are heterozygous for the deletion mutation of MSH2 gene (MSH2+/MSH2-) from birth are very likely to develop colon cancer very early in their lives?arrow_forwardHeritable effects of gene expression that are not caused by a change in DNA sequence are called epigenic changes. What causes these changes?arrow_forwardThe genetic alteration responsible for sickle-cell anemia in humans involves: a transition mutation from A to G, substituting glutamic acid for valine in a-globin a transversion mutation from T to A, substituting valine for glutamic acid in b-globin a transition mutation from T to C, substituting valine for glutamic acid in b-globin a transversion mutation from G to C, substituting glutamic acid for valine in a-globin a frameshift mutation of one ATC codon, removing glutamic acid from b-globinarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education
Mitochondrial mutations; Author: Useful Genetics;https://www.youtube.com/watch?v=GvgXe-3RJeU;License: CC-BY