4. Consider a pair of monozygotic twins, both are XY individuals (monozygotic = originated from the same zygote). One was healthy and the other showed symptoms of hemophilia related to loss-of-function of F8 (recall F8 locus is on the X chromosome, not in the pseudo autosomal region). a. Propose a way that these two twins have a different F8 phenotype despite arising from the same zygote? b. Consider XX monozygotic twins that came from a zygote that was +/- for the F8 locus. Is it possible that a mitotic non-disjunction could result in one twin developing hemophilia and the other not have hemophilia? Use a drawing to help explain your answer.

4. Consider a pair of monozygotic twins, both are XY individuals (monozygotic = originated from the same zygote). One was healthy and the other showed symptoms of hemophilia related to loss-of-function of F8 (recall F8 locus is on the X chromosome, not in the pseudo autosomal region). a. Propose a way that these two twins have a different F8 phenotype despite arising from the same zygote? b. Consider XX monozygotic twins that came from a zygote that was +/- for the F8 locus. Is it possible that a mitotic non-disjunction could result in one twin developing hemophilia and the other not have hemophilia? Use a drawing to help explain your answer.

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter13: Genes, Chromosomes, And Human Genetics

Section: Chapter Questions

Problem 9TYK

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Similar questions

Why is it more efficient to perform a test cross with a homozygous recessive donor than a homozygous dominant donor? How could the same information still he found with a homozygous dominant donor?
In addition to the two genes in problem 4, assume you now study a third independently assorting gene that has the alleles C and c. For each of the following genotypes, indicate what types of gametes will be produced: a. AA BB CC b. Aa BB Cc c. Aa BB cc d. Aa Bb Cc
Refer to problem 2. Assume a third gene has alleles C and c. For each genotype listed, what allele combinations will occur in gametes, assuming independent assortment? a. AABBCC b. AaBBcc c. AaBBCc d. AaBbCc
The probability of a crossover occurring between two genes on the same chromosome ________. a. is unrelated to the distance between them b. decreases with increasing distance between them c. Increases with the distance between them
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5. A strain of Neurospora with genotype A B is crossed with a strain with the genotype a b. Half the progeny are A B and half are a b. Explain how this is possible?
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1. Why is the relationship P=p2 used for homozygous loci?
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