Chapter 4, Problem 30PDQ

Consider the three pedigrees below, all involving a single human trait.

1. (a) Which combination of conditions, if any, can be excluded?

   dominant and X-linked

   dominant and autosomal

   recessive and X-linked

   recessive and autosomal

2. (b) For each combination that you excluded, indicate the single individual in generation II (e.g., II-1, II-2) that was most instrumental in your decision to exclude it. If none were excluded, answer “none apply.”

1. (c) Given your conclusions in part (a), indicate the genotype of the following individuals:

   II-1, II-6, II-9

If more than one possibility applies, list all possibilities. Use the symbols A and a for the genotypes.