8. Phenylketonuria (PKU) is an inherited disease caused by a recessive allele. If a woman and her husband are both carriers, what is the probability of each of the following? Justify your answers with a Punnett Square. a. That they will have a child with the disease?

8.     Huntington’s disease is a degenerative disease of the nervous system that strikes in middle age. The allele that causes the disease (H) is dominant to the allele that results in the normal condition (h). Answer the following questions about the inheritance of this disease. A.     What is the genotype of a man who is normal but whose father had Huntington’s disease?   B.     What is the genotype of a woman who has Huntington’s disease if both of her parents had Huntington’s disease?   C.     If a man who is heterozygous for Huntington’s disease marries a woman who is normal, what would you expect for the genotypes and phenotypes of their children? D.     If a normal man marries a woman who is homozygous for Huntington’s disease, what do you expect for the genotypes and phenotypes of their children?

I understand that Phenylketonuria, or PKU is recessive and that by looking at the pedigree analysis that Ryan and Natalie are mother/son, but I don't understand the genotypes for Max and Kate.   Thanks for any help.

问题13 Achondroplasia (dwarfism) is an example of a dominantly inherited disease. Individuals who have the dominant gene (A) have the dwarfism phenotype, while normal height is recessive (a). What is the probability of having children with achondroplasia between a normal height female and a heterozygote achondroplasia male? 100% 75% 25% 50%

1. Hemophilia is due to a sex-linked gene. It is recessive and found on the X chromosome. A woman who is a carrier for hemophilia marries a normal man. What will be the possible phenotypes of their children? Use a punnet square. 2. A phenotypically normal man, who has a hemophiliac brother, marries a normal woman, who is not a carrier. What is the probability that any of their children will be hemophiliac? Use a punnet square. 3. Color-blindness is an X-linked, recessive trait. If a normal-sighted woman, whose father was color-blind, marries a colorblind man, what is the probability that they will have a son who is color-blind? Use a punnet square. 4. A man and woman, both of normal vision, have:  1) a color-blind son (#1) who has a daughter of normal vision  2) a daughter (#1) of normal vision who has one color-blind son and one normal vision son  3) another daughter (#2) of normal vision who has five sons, all with normal vision  What are the probable genotypes of the…

Now assume that the pedigree shown in question 1 shows the inheritance of a rare genetic disease. a) The disease is most likely autosomal dominant b) The disease is most likely autosomal recessive c) The disease is equally likely to be either autosomal dominant or autosomal recessive, but cannot be x-linked d) Cannot be determined from the information given

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A couple finds out that both the male and the female are heterozygotes (carriers) for Tay Sachs. Draw a punnet square for this couple. What is the likelihood that this couple will have an offspring with Tay Sachs?