Question

J and K want to have a baby, but they are a little concerned because they both have the sickle cell trait. They want to know what the possibility is that their child may actually have the disease.
1. Develop a Punnett square depicting the possibility that their offspring will have the trait and/or the disease.

2.How would the nurse interpret this Punnett square?

Answer 1

Answer:

1. Attached

2. The have a 25% possibility of the disease and a 50% possibility of having the trait.

Explanation:

1. If J and K both carry the sickle cell trait, that means they are heterozygous for the sickle cell allele (Ss) where the sickle cell allele is recessive to the normal allele. The punnet square showing the possible genotypes of their potential offspring is shown in the attachment

2. The nurse would see that the genotypes possible are SS, Ss, or ss. SS would be a normal phenotype, Ss would be sickle cell trait, like the parents, and ss would have sickle cell disease. The ratios are 1 SS: 2 Ss: 1 ss. This means there is a 25% chance the child will be totally normal, a 50% chance they will inherit sickle cell trait, and 25% chance the child will have sickle cell disease.

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