Question

A child has sickle-cell disease (ss) but neither parent is ill. what must be true of her parents’ genotypes?

Answer 1

Answer;

-Both parents are carriers of the sickle cell genes, they have one sickle cell gene and thus they do not show the trait.

Explanation;

-Sickle Cell Anemia is an autosomal recessive trait. This means that in order for the trait to be shown, both parents of an individual must carry at least one sickle cell gene.

- A child with this disorder can be born to parents who do not have the disorder because the parents must have at least one gene, but do not have two and therefore do not show the trait. Since it is recessive, in order to show the trait, you must have two of the genes.

Answer 2

Sickle cell is recessive. Neither parent is ill of sickle cell disease (not mentioned in the question), but the parent's genotypes carry the trait which they passed on to their child. This is what is true of the parent's genotypes. Hope my answer has come to your help.