Concept explainers
Both members of a couple know that they are carriers of the cystic fibrosis allele. None of their three children has cystic fibrosis, but any one of them might be a carrier The couple would like to have a fourth child but are worried that he or she would very likety have the disease, since the first three do not. What would you tell the couple? Would it remove some uncertainty from their prediction if they could find out whether the three children are carriers?
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Genetics: Analysis and Principles
Becker's World of the Cell (9th Edition)
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Fundamentals of Anatomy & Physiology (11th Edition)
Genetic Analysis: An Integrated Approach (2nd Edition)
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- Duchenne muscular dystrophy is sex linked and usuallyaffects only males. Victims of the disease become progressively weaker, starting early in life.a. What is the probability that a woman whose brotherhas Duchenne’s disease will have an affected child?b. If your mother’s brother (your uncle) had Duchenne’sdisease, what is the probability that you have receivedthe allele?c. If your father’s brother had the disease, what is theprobability that you have received the allele?arrow_forwardA healthy young couple, Charlie and Eva, both with families histories of cystic fibrosis, visits a genetic counselor before deciding whether to have children. The genetic counselor analyzed their pedigree to determine if they are carriers of the alleles for cystic fibrosis. On a sheet of paper, draw the given pedigree chart below and label each individual with the correct genotype.arrow_forwardFrank and Susan both have freckles but they're firstborn son Lawrence does not demonstrate the characteristics. What are the most likely genotype of Frank Susan and Lawrence?arrow_forward
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