Chapter 5, Problem 34P

The accompanying pedigree below shows a family in which an autosomal recessive disorder is presents. Family members $\text{I-2}$ and $\text{II-2}$ are affected by the disorder and have te genotype dd. A pregnancy involving $\text{II-4}$ has just undergone genetic testing for a VNTR that is linked to the disease gene. The VNTR has a recombination frequency of $\text{ r = 0}\text{.20}$ with the disease gene. The VNTR has two alleles, $\text{V1}$ and $\text{V2}$. The gel electrophoresis patterns for each family members are shown, including the VNTR genotype for $\text{II-4}$. Based on the information given, answer the following questions about the family.

Excluding $\text{II-4}$, what is the genotype of each family members for the disease for the disease gene?

What is the genotype of each family member, including $\text{II-4}$, for the VNTR?

What are the synthetic disease gene and VNTR alleles in $\text{I-1}$ and $\text{I-2}$?

What is the chance $\text{II-4}$ has the disease?