ESSENTIALS OF GENETICS-W/MOD.ACCESS
9th Edition
ISBN: 9780134452876
Author: KLUG
Publisher: PEARSON
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Chapter 20, Problem 2CS
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.
How can two clinically different disorders result from the same mutation?
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Chapter 20 Solutions
ESSENTIALS OF GENETICS-W/MOD.ACCESS
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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- In drosophila, a recessive mutation (m-) of a maternal effect gene results in an abnormal phenotype wherein homozygous (m-m-) females produce eggs that cannot support embryonic development. Homozygous (m-m-) males, however, can still produce viable sperm. Using m+ to denote a normal gene, determine the genotypes and phenotypes of the F1s produce by a cross between a heterozygous female and a recessive male. From the offspring, backcross the recessive female with the paternal strain. What are the genotypes and phenotypes of the F2s? Show COMPLETE cross for both cases. If m-m- females produce useless eggs, then how are m-m- produced?arrow_forwardmapping gene The genes for ruby eyes (rb), tan body (t) and cut wings (ct) are all found on the X-chromosome of Drosophila melanogaster. All of these are recessive traits. They map in the order rb, ct, t with 12.5 map units between rb and ct and 7.5 map units between ct and t. Suppose you cross a cut wing male with a homozygous female that is both tan and has ruby eyes. What will the F1 females look like? Draw map of the section of the X chromosomes that has these 3 genes for the F1 females Assume you testcross your F1 females. What progeny classes would you expect? ii. Give approximate numbers for each class based on a total of 2000 progeny. Assuming the i=1 and there are no double crossovers. Assuming the i=0 and there are the expected number of double crossovers.arrow_forward2. a. You want to create a genetic construct that will express GFP in Drosophila. In addition to the GFPcoding sequence, what DNA element(s) must youinclude in order to express this protein in flies if theconstruct were integrated into the Drosophila genome? Where should such DNA element(s) be located? How would you ensure that GFP is expressedonly in certain tissues of the fly, such as the wing?b. Suppose you insert the GFP coding region plus allof the DNA elements required by the answer to part(a)—except the enhancer—between inverted repeatsfound at the ends of a particular transposable element.Because all of the DNA sequences located betweenthese inverted repeats can move from place to placein the Drosophila genome, you can generate manydifferent fly strains, each with the construct integrated at a different genomic location. You now examine animals from each strain for GFPfluorescence. Animals from different strains showdifferent patterns: some glow green in the eyes,others in…arrow_forward
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- Interested in exploring the genetic pathways that lead to neurological issues, you want to see if recessive mutations which generate too many neurons (tm) in flies - which many causes autistic like symptoms are in the same gene as mutations that generate too few neurons (tf) - intellectual diabilities. You cross a true-breeding homozygous tm/tm fly to a homozygous too few neuron fly tf/tf. What phenotype in the progeny would tell these mutations are in different genes?arrow_forwardMale Drosophila expressing the autosomal recessivemutations sc (scute), ec (echinus), cv (crossveinless),and b (black) were crossed to phenotypically wildtype females, and the 3288 progeny listed wereobtained. (Only mutant traits are noted.)653 black, scute, echinus, crossveinless670 scute, echinus, crossveinless675 wild type655 black71 black, scute73 scute73 black, echinus, crossveinless74 echinus, crossveinless87 black, scute, echinus84 scute, echinus86 black, crossveinless83 crossveinless1 black, scute, crossveinless1 scute, crossveinless1 black, echinus1 echinusa. Diagram the genotype of the female parent.b. Map these loci.c. Do the data provide evidence of interference?Justify your answer with numbers.arrow_forwardQ11. One of the two genes known to be mutated in cases of Hypokalemic periodic paralysis (which is inherited in an autosomal dominant pattern but known to affect males more often than females) is the calcium voltage-gated channel subunit alpha1 S (CACNA1S). What is known about the gene is recorded here: https://www.ensembl.org/Homo_sapiens/Gene/Summary?db=core;g=ENSG00000081248;r=1:201039512-201112451 Please navigate to the link above and ensure that you click to reveal the transcript table. Then use the information in the table to answer the following question. What is the NCBI accession number (including the version) of the RefSeq Match for the first transcript (CACNA1S-201)? Answer: NCBI accession number (including the version) of the RefSeq Match for the first transcript (CACNA1S-201) is ...arrow_forward
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