Chapter 3, Problem 3PDQ

Albinism in humans is inherited as a simple recessive trait. For the following families, determine the genotypes of the parents and offspring. (When two alternative genotypes are possible, list both.)

1. (a) Two normal parents have five children, four normal and one albino.
2. (b) A normal male and an albino female have six children, all normal.
3. (c) A normal male and an albino female have six children, three normal and three albino.
4. (d) Construct a pedigree of the families in (b) and (c). Assume that one of the normal children in (b) and one of the albino children in (c) become the parents of eight children. Add these children to the pedigree, predicting their phenotypes (normal or albino).