Ch. 13-7 Mutations in the TYR gene may render its enzyme product—tyrosinase—nonfunctional.Individuals homozygous for such mutations cannot make the pigment melanin. Albinism, the absence of melanin, results. Humans and many other organisms can have this phenotype (right). Mutated tyrosinase alleles are recessive when paired with the normal allele in heterozygous individuals.In the following situations, what are the probable genotypes of the father, the mother, and their children?a. Both parents have normal phenotypes; some of their children have the albino phenotype and others are unaffected.b. Both parents and children have the albino phenotype.c. The mother and three children are unaffected; the father and one child have the albino phenotype.

Ch. 13-7 Mutations in the TYR gene may render its enzyme product—tyrosinase—nonfunctional.Individuals homozygous for such mutations cannot make the pigment melanin. Albinism, the absence of melanin, results. Humans and many other organisms can have this phenotype (right). Mutated tyrosinase alleles are recessive when paired with the normal allele in heterozygous individuals.In the following situations, what are the probable genotypes of the father, the mother, and their children?a. Both parents have normal phenotypes; some of their children have the albino phenotype and others are unaffected.b. Both parents and children have the albino phenotype.c. The mother and three children are unaffected; the father and one child have the albino phenotype.

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Description: Ch. 13-7Mutations in the TYR gene may render its enzyme product—tyrosinase—nonfunctional.Individuals homozygous for such mutations cannot make the pigment melanin. Albinism, the absence of melanin, results. Humans and many other organisms can have th

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter11: Genome Alterations: Mutation And Epigenetics

Section: Chapter Questions

Problem 16QP: Familial retinoblastoma, a rare autosomal dominant defect, arose in a large family that had no prior...

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Six months pregnant, an expectant mother had a routineultrasound that showed that the limbs of the fetus wereunusually short. Her physician suspected that the babymight have a genetic form of dwarfism called achondroplasia,an autosomal dominant trait occurring with a frequency of about1 in 27,000 births. The parents were directed to a genetic counselorto discuss this diagnosis. In the conference, they learnedthat achondroplasia is caused by a mutant allele. Sometimes itis passed from one generation to another, but in 80 percent ofall cases it is the result of a spontaneous mutation that arisesin a gamete of one of the parents. They also learned that mostchildren with achondroplasia have normal intelligence and a normallife span. It has been suggested that prenatal genetic testing for achondroplasiabe made available and offered to all women. Wouldyou agree with this initiative? What ethical considerationswould you consider when evaluating the medical and societalconsequences of offering…
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