EBK GENETICS: FROM GENES TO GENOMES
6th Edition
ISBN: 9781260041255
Author: HARTWELL
Publisher: MCGRAW HILL BOOK COMPANY
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Chapter 11, Problem 35P
The drug ivacaftor has recently been developed to treat cystic fibrosis in children with the rare G551D mutant allele of CFTR.
| a. | Do you think that ivacaftor would be effective only in patients homozygous for the G551D mutation, or might it work as well in compound heterozygotes in which one copy of chromosome 7 had G551D and the other copy a different allele of CFTR, such as the more prevalent allele ΔF508? (The protein encoded by G551D folds up properly and inserts into the cell membrane, but is inefficient in chloride ion transport. Ivacaftor increases the efficiency of G551D’s ion transport. The ΔF508 protein does not fold up properly and therefore does not get inserted into the cell membrane.) |
| b. | Why do you think ivacaftor would be more effective in children than in older cystic fibrosis patients? |
| c. | The scientists who developed ivacaftor had a model for cystic fibrosis: a line of cells that grow in culture and that are homozygous for G551D. These cells accumulate mucus at their surfaces that prevent cilia (tiny hairs on the outside of cells) from beating. Explain how the scientists could use this disease model to screen for drugs that would be effective against G551D-associated cystic fibrosis. |
| d. | Ivacaftor is used in combination with an even newer drug called lumacaftor to treat individuals homozygous for the most common CF allele, ΔF508. Lumacaftor helps the ΔF508 mutant CFTR protein fold properly so that it can insert in the cell membrane. Why do you think that neither lumacaftor nor ivacaftor alone are effective in treating ΔF508 homozygotes, while the combination of both drugs is effective? |
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Chapter 11 Solutions
EBK GENETICS: FROM GENES TO GENOMES
Ch. 11 - Choose the phrase from the right column that best...Ch. 11 - Would you characterize the pattern of inheritance...Ch. 11 - Would you be more likely to find single nucleotide...Ch. 11 - A recent estimate of the rate of base...Ch. 11 - If you examine Fig. 11.5 closely, you will note...Ch. 11 - Approximately 50 million SNPs have thus far been...Ch. 11 - Mutations at simple sequence repeat SSR loci occur...Ch. 11 - Humans and gorillas last shared a common ancestor...Ch. 11 - In 2015, an international team of scientists...Ch. 11 - Using PCR, you want to amplify an approximately 1...
Ch. 11 - Prob. 11PCh. 11 - The previous problem raises several interesting...Ch. 11 - You want to make a recombinant DNA in which a PCR...Ch. 11 - You sequence a PCR product amplified from a...Ch. 11 - Prob. 15PCh. 11 - The trinucleotide repeat region of the Huntington...Ch. 11 - Sperm samples were taken from two men just...Ch. 11 - Prob. 18PCh. 11 - a. It is possible to perform DNA fingerprinting...Ch. 11 - On July 17, 1918, Tsar Nicholas II; his wife the...Ch. 11 - The figure that follows shows DNA fingerprint...Ch. 11 - Microarrays were used to determine the genotypes...Ch. 11 - A partial sequence of the wild-type HbA allele is...Ch. 11 - a. In Fig. 11.17b, PCR is performed to amplify...Ch. 11 - The following figure shows a partial microarray...Ch. 11 - Scientists were surprised to discover recently...Ch. 11 - The microarray shown in Problem 25 analyzes...Ch. 11 - The figure that follows shows the pedigree of a...Ch. 11 - One of the difficulties faced by human geneticists...Ch. 11 - Now consider a mating between consanguineous...Ch. 11 - The pedigree shown in Fig. 11.22 was crucial to...Ch. 11 - You have identified a SNP marker that in one large...Ch. 11 - The pedigrees indicated here were obtained with...Ch. 11 - Approximately 3 of the population carries a mutant...Ch. 11 - The drug ivacaftor has recently been developed to...Ch. 11 - In the high-throughput DNA sequencing protocol...Ch. 11 - A researcher sequences the whole exome of a...Ch. 11 - As explained in the text, the cause of many...Ch. 11 - Figure 11.26 portrayed the analysis of Miller...Ch. 11 - A research paper published in the summer of 2012...Ch. 11 - Table 11.2 and Fig. 11.27 together portray the...Ch. 11 - The human RefSeq of the entire first exon of a...Ch. 11 - Mutations in the HPRT1 gene in humans result in at...Ch. 11 - Prob. 44P
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