Practice Pedigree 1:

​In humans, albinism is a recessive trait. The disorder causes a lack of pigment in the skin and hair, making an albino appear very pale with white hair and pale blue eyes. This disorder can also occur in animals, a common albino found in a laboratory is the white rat. The pedigrees below trace the inheritance of the allele that causes albinism.

​1.  Number the generations and individuals.

2. In this family, how many individuals “show” the trait? & who are they?

3. How many men show the trait?

4. How many children does the couple from the first generation have?

Pedigree Practice 2:

In humans, albinism is a recessive trait. The disorder causes a lack of pigment in the skin and hair, making an albino appear very pale with white hair and pale blue eyes. This disorder can also occur in animals, a common albino found in a laboratory is the white rat. The pedigrees below trace the inheritance of the allele that causes albinism.

1. Given the following genotypes, describe the phenotypes

(normal or albino)

AA = ____________________

Aa = ____________________

aa = _____________________

2. Label the generations and
individuals.

3. Figure out all the genotypes of each
individual given that all shaded shapes
express the trait.

​Pedigree Analysis

a) How many children did the original couple have?  _____

b) How many grandchildren? _____

c) How many of their grandchildren are albino?  ______

d) Create an extension to the pedigree to show the albino granddaughter marrying and having a son who is NOT albino.