Biomorph
Challenge #3 |
Population Genetics
The Chief
Spin Officer was fired because you answered so promptly.
A message from the new Chief Spin Officer of the Biomorph mothership:
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"Our advanced Biomorph genomes contain a special allele for Interspecies Cooperation, which is dominant to the recessive allele. Since the Interspecies Cooperation allele is dominant, its frequency will increase in our population, and any problems we have getting along with you will soon disappear." |
What do you say?
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Quiz: Respond Online
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Written assignment -- turn in to professor
1. ABO blood types result from 3 possible alleles: i, IA and IB in most populations. The blood types that result from the pairing of alleles is as follows:
Thus, we have 3 alleles (versions of the gene), 6 genotypes (arrangement of alleles) and 4 phenotypes (physical result of genes). a. If a person with O blood type marries a person with AB blood type, what is the % chance that they could produce a child with blood type AB? b. A child with blood type A? c. If the person with O blood type marries a person with genotype IA IA or IB i, their offspring may have which possible genotypes and phenotypes? Predicted % occurance? d. Which combination of parent blood genotypes would have the greatest variety possible in their offspring. Illustrate your thinking process. 2. a. From the information you can find in the text of Galapagos, draw the family tree of the captain von Kleist and his brother. Define and include an appropriate genotype designation for each person. b. What do you think would happen in the unlikely event of a person inheriting the gene for Huntington’s disease from both his parents? c. Consider a hypothetical sister of Adolf and Sigfried. What are the possible genotypes for her and what chance does she have of having the disease? d. You are a genetic counselor, and you are visited by a young person whose father died of Huntington’s disease who was planning to marry someone who did not have the disease in her family. What would you advise them and why? A DNA test now exists to detect whether one carries the Huntington allele. How would this change your advice?
4. Retinitis pigmentosa is an X-linked disease causing blindness. Selena was blind from this disease, because her mother was a carrier, her father was normal. What did the author get wrong? (Look up in OMIM.) What chance does she have of passing on the disease? 5. Akiko had especially hairy skin, a condition called hypertrichosis. Based on the description in the book, and information you find in OMIM, what genetic trait do you think she might have had and why? (Various answers possible.) 6. Researchers have identified an allele of a gene that confers resistance to HIV virus, the cause of AIDS. The allele is a version of the CCR5 gene that has part of its sequence deleted (allele CCR5-delta 32). The CCR5-delta 32 allele is present at a frequency of 0.10 in the Caucasian population of the United States. Persons who are homozygous recessive (aa) show virtually complete resistance to HIV, and those who are heterozygous (Aa) have 78% lower risk of HIV infection. Those who are homozygous dominant (AA) have no resistance to HIV. Find the percentages of the US Caucasian population that exhibit the 3 possible phenotypes. 7. Explain how each of the following traits is determined by genes and/or environment: * The shell of a tortoise |