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
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Chapter 20, Problem 3CS
CASE STUDY| One foot or another
In humans the HOXD homeotic gene cluster plays a critical role in limb development. In one large family, 16 of 36 members expressed one of two dominantly inherited malformations of the feet known as rocker bottom foot (CVT) or claw foot (CMT). One individual had one foot with CVT and the other with CMT. Genomic analysis identified a single missense mutation in the HOXD10 gene, resulting in a single amino acid substitution in the homeodomain of the encoded transcription factor. This region is crucial for making contact and binding to the target genes controlled by this protein. All family members with the foot malformations were heterozygotes; all unaffected members were homozygous for the normal allele.
What might we learn about the control of developmental processes from an understanding of how this mutation works?
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Part 3C: Below is data from a pedigree trace of patients affected with mouse model of pancreatic
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Patient II-4 has two copies of loss of function variant alleles (or is homozygous for loss-of-function
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Patient I-2 has one copy of loss of function variant and one copy of unaffected allele (is
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Patient II-1 has two copies of unaffected allele (or is homozygous for unaffected 318 allele).
|-1
1-2
Il-1
Il-2
Il-3
|l-4
II-5
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III-2
III-3
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Fragile X syndrome
why is interesting Fragile X syndrome
What are the symptoms or characteristics of this disorder or trait?
What is the prevalence of the trait or disorder?
What are the main genetic factors?
s the genetic cause of this disorder or trait known? What gene(s) have been proven to be involved? Or, if not known, what genes are thought to be involved? Is it caused by a single gene? polygenic? Multifactorial?
Devote a few paragraphs to this
This could be one of the longest parts of the paper, if you choose to focus on this.
If multiple genes are thought to be involved, discuss the specific role of at least one of them in depth (if known). Is the gene you’re discussing thought to play a major or a minor role in the phenotype? What chromosome is it on? What protein does it code for, and how might the protein possibly contribute to the phenotype?
If no genes have yet been identified, indicate this, and devote at least one paragraph to any current efforts to determine which…
Chapter 20 Solutions
Essentials of Genetics (9th Edition) - Standalone book
Ch. 20 -
CASE STUDY |One foot or another
In humans the...Ch. 20 - CASE STUDY| One foot or another In humans the HOXD...Ch. 20 - CASE STUDY| One foot or another In humans the HOXD...Ch. 20 - HOW DO WE KNOW? In this chapter, we have focused...Ch. 20 - Review the Chapter Concepts list on page 403. Most...Ch. 20 -
3. Nuclei from almost any source may be injected...Ch. 20 -
4. Distinguish between the syncytial blastoderm...Ch. 20 - (a) What are maternal-effect genes? (b) When are...Ch. 20 - (a) What are zygotic genes, and when are their...Ch. 20 - List the main classes of zygotic genes. What is...
Ch. 20 -
8. Experiments have shown that any nuclei placed...Ch. 20 - How can you determine whether a particular gene is...Ch. 20 -
10. You observe that a particular gene is being...Ch. 20 - What are Hox genes? What properties do they have...Ch. 20 -
12. The homeotic mutation Antennapedia causes...Ch. 20 - The Drosophila homeotic mutation spineless...Ch. 20 - A number of genes that control expression of Hox...Ch. 20 - In Arabidopsis, flower development is controlled...Ch. 20 - Prob. 16PDQCh. 20 - Dominguez et al. (2004) suggest that by studying...
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