Homework Help is Here – Start Your Trial Now!
Science
Biology
22. Scientists now routinely use CRISPR/Cas9 to make defined deletions of a gene that can remove several kb of DNA from the genome. This method is possible even in cells defective in homologous recombination, as long as the cells can still perform nonhomologous end- joining (NHEJ). a. How could researchers make such deletions? b. A GM animal that may be approved for human consumption by the time this book is published is a “super-muscly" pig made by inactivation of the myostatin gene. Page 643 During normal development, Myostatin protein prevents the overgrowth of muscles. Given your answer to part (a), how could the super-muscly pig have been generated?

22. Scientists now routinely use CRISPR/Cas9 to make defined deletions of a gene that can remove several kb of DNA from the genome. This method is possible even in cells defective in homologous recombination, as long as the cells can still perform nonhomologous end- joining (NHEJ). a. How could researchers make such deletions? b. A GM animal that may be approved for human consumption by the time this book is published is a “super-muscly" pig made by inactivation of the myostatin gene. Page 643 During normal development, Myostatin protein prevents the overgrowth of muscles. Given your answer to part (a), how could the super-muscly pig have been generated?

Human Anatomy & Physiology (11th Edition)
Human Anatomy & Physiology (11th Edition)
11th Edition
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:Elaine N. Marieb, Katja N. Hoehn
Chapter1: The Human Body: An Orientation
Section: Chapter Questions
Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...
See similar textbooks
icon
Related questions
Question
 
a gm animal that may be approved for human consumption by the time this book is published is a super muscly pig made by inactivation of the myostatin gene. During normal development, myostatin protein prevents the overgrowth of muscles. (Given that effective deletions can be made in the genome by using CRISPR/Cas9. It targets deletions of varied length. By this technique, the transcriptional status of the target gene is not affected. The gene deletions produced by CRISPR/Cas9 lead to the production of the correct type of junctions at very high frequencies), how could the super muscly pig have been generated?
Answer the questions in the photo as well. ( i included my answer for 22a in the question above, if you believe you have a better answer by all means include that as well)


 
 
 
 
 
35. Recently, scientists have used a mouse model for Duchenne muscular dystrophy (called the mdx mouse) to test whether Cas9 and an sgRNA could be an effective therapy for this disease. The cause of muscular dystrophy is homozygosity or hemizygosity for loss-of- function mutations in the X-linked Dmd gene. The mdx mouse has a nonsense mutation in exon 23 (of 79 exons) of Dmd. Researchers tested a technique called exon skipping; their idea was to use CRISPR/Cas9 to delete exon 23 in the mutant Dmd gene in the mdx mouse. AAV vectors with genes that express Cas9 and two different sgRNAs were injected into the muscles of adult mice. In about 10% of the muscle cells, exon 23 was deleted, and functional dystrophin protein was detected. Some muscle function was restored, although only to a small extent. a. Draw a diagram of exon 23 and the introns that flank it. On your diagram, draw the locations where the sgRNAs would hybridize with the genomic DNA. Explain how the deletion of exon 23 would take place. b. Design a PCR assay to determine if exon 23 is deleted from the genomic DNA of cell clones. Where would the PCR primers hybridize, and how would you be able to tell if the exon was deleted? c. Skipping exon 23 restored dystrophin protein function at least partially. What does this say about the amino acids encoded by exon 23? d. Considering your answer to part (c), would the exon-skipping strategy work for all Dmd point mutations that cause muscular dystrophy? e. What must be true about exons 22, 23, and 24 that would allow the researchers to consider this exon-skipping strategy? (Hint: See Problems 28 (9 and 29 9.)
Transcribed Image Text:35. Recently, scientists have used a mouse model for Duchenne muscular dystrophy (called the mdx mouse) to test whether Cas9 and an sgRNA could be an effective therapy for this disease. The cause of muscular dystrophy is homozygosity or hemizygosity for loss-of- function mutations in the X-linked Dmd gene. The mdx mouse has a nonsense mutation in exon 23 (of 79 exons) of Dmd. Researchers tested a technique called exon skipping; their idea was to use CRISPR/Cas9 to delete exon 23 in the mutant Dmd gene in the mdx mouse. AAV vectors with genes that express Cas9 and two different sgRNAs were injected into the muscles of adult mice. In about 10% of the muscle cells, exon 23 was deleted, and functional dystrophin protein was detected. Some muscle function was restored, although only to a small extent. a. Draw a diagram of exon 23 and the introns that flank it. On your diagram, draw the locations where the sgRNAs would hybridize with the genomic DNA. Explain how the deletion of exon 23 would take place. b. Design a PCR assay to determine if exon 23 is deleted from the genomic DNA of cell clones. Where would the PCR primers hybridize, and how would you be able to tell if the exon was deleted? c. Skipping exon 23 restored dystrophin protein function at least partially. What does this say about the amino acids encoded by exon 23? d. Considering your answer to part (c), would the exon-skipping strategy work for all Dmd point mutations that cause muscular dystrophy? e. What must be true about exons 22, 23, and 24 that would allow the researchers to consider this exon-skipping strategy? (Hint: See Problems 28 (9 and 29 9.)
22. Scientists now routinely use CRISPR/Cas9 to make defined deletions of a gene that can remove several kb of DNA from the genome. This method is possible even in cells defective in homologous recombination, as long as the cells can still perform nonhomologous end- joining (NHEJ). a. How could researchers make such deletions? b. A GM animal that may be approved for human consumption by the time this book is published is a “super-muscly" pig made by inactivation of the myostatin gene. Page 643 During normal development, Myostatin protein prevents the overgrowth of muscles. Given your answer to part (a), how could the super-muscly pig have been generated?
Transcribed Image Text:22. Scientists now routinely use CRISPR/Cas9 to make defined deletions of a gene that can remove several kb of DNA from the genome. This method is possible even in cells defective in homologous recombination, as long as the cells can still perform nonhomologous end- joining (NHEJ). a. How could researchers make such deletions? b. A GM animal that may be approved for human consumption by the time this book is published is a “super-muscly" pig made by inactivation of the myostatin gene. Page 643 During normal development, Myostatin protein prevents the overgrowth of muscles. Given your answer to part (a), how could the super-muscly pig have been generated?
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps

SEE SOLUTIONCheck out a sample Q&A here
Blurred answer
Knowledge Booster
Genome annotation
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
Recommended textbooks for you
Human Anatomy & Physiology (11th Edition)
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:
9780134580999
Author:
Elaine N. Marieb, Katja N. Hoehn
Publisher:
PEARSON
Biology 2e
Biology 2e
Biology
ISBN:
9781947172517
Author:
Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:
OpenStax
Anatomy & Physiology
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)
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
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)
Inquiry Into Life (16th Edition)
Biology
ISBN:
9781260231700
Author:
Sylvia S. Mader, Michael Windelspecht
Publisher:
McGraw Hill Education
SEE MORE TEXTBOOKS