Question

6.Two apparently normal parents have a daughter who suffers from agammaglobulinemia (AGG), an inherited defect of the immune system. Use a Punnett square to show how two normal parents could have a child afflicted with an inherited disease. What are the parents' genotypes

Answer 1

Answer:

See the answer below

Explanation:

For two normal parents to have produced a daughter who suffers from AGG, it means the disorder is an autosomal recessive trait. In order words, it means the parents are both carrying the allele for the disorder in recessive form.

Let us assume that the allele for the disorder is represented by b, meaning that the alternate form would be B. Both parents will have the genotype Bb and will both appear normal.

      Bb    x    Bb

    BB   Bb   Bb   bb

The affected child would be the one with bb genotype while the remaining children would appear normal. See the attached image for the Punnet's square analysis of the cross.

The genotypes of the parent would be heterozygous.