Concepts of Genetics (12th Edition)
12th Edition
ISBN: 9780134604718
Author: William S. Klug, Michael R. Cummings, Charlotte A. Spencer, Michael A. Palladino, Darrell Killian
Publisher: PEARSON
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Textbook Question
Chapter 19, Problem 21ESP
Prader–Willi syndrome (PWS) is a genetic disorder with a clinical profile of obesity, intellectual disability, and short stature. It can be caused in several ways. Most common is a deletion on the paternal copy of chromosome 15, but it can also be caused by an epigenetic imprinting disorder, and uniparental disomy, an event in which the affected child receives two copies of the maternal chromosome 15. A child with PWS comes to your clinic for a diagnosis of the molecular basis for this condition. The gel below shows the results of testing with short tandem repeats (STRs) from the region of chromosome 15 associated with the disorder.
- (a) Is this case caused by a deletion in the paternal copy of chromosome 15? Explain.
- (b) Based on your interpretation of the data, what is the cause of PWS in this case? Explain your reasoning.
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Duchenne 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).
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Chapter 19 Solutions
Concepts of Genetics (12th Edition)
Ch. 19 - Although histone modifications can activate or...Ch. 19 - Prob. 2NSTCh. 19 - Prob. 1CSCh. 19 - Prob. 2CSCh. 19 - A couple well informed about the epigenetic...Ch. 19 - Prob. 1PDQCh. 19 - Prob. 2PDQCh. 19 - Prob. 3PDQCh. 19 - Prob. 4PDQCh. 19 - Prob. 5PDQ
Ch. 19 - Prob. 6PDQCh. 19 - Prob. 7PDQCh. 19 - Prob. 8PDQCh. 19 - Prob. 9PDQCh. 19 - Prob. 10PDQCh. 19 - What are the functions of IncRNAs in epigenetic...Ch. 19 - Prob. 12PDQCh. 19 - What are the differences and similarities among...Ch. 19 - Prob. 14PDQCh. 19 - Prob. 15PDQCh. 19 - Should fertility clinics be required by law to...Ch. 19 - Prob. 17PDQCh. 19 - Prob. 18PDQCh. 19 - A developmental disorder in humans called spina...Ch. 19 - Prob. 20PDQCh. 19 - PraderWilli syndrome (PWS) is a genetic disorder...Ch. 19 - Prob. 22ESPCh. 19 - Prob. 23ESPCh. 19 - Methylation of H3K9 by itself silences genes, but...
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