Question

Ahmad and Suha are planning a family, but since each has a brother who has sickle-cell anemia, they are concerned that their children may develop sickle-cell disease, Neither Ahmad, Suha nor their respective parents have the disease. They consult a genetic counselor who tells them __________

• A. There is very little chance that any of their children will have sickle cell disease
• B. That all of their children will have sickle-cell disease
• C. That one out of four off their children could be expected to have sickle-cell disease
• D. That its possible that none of their children will have the disease but blood tests on them both will be required to make sure

Answer 1

The correct option is A There is very little chance that any of their children will have sickle cell disease

Sickle cell anemia is a autosomal recessive disorder. A person requires two set of defective allele to inherit sickle-cell disease. In the given case, brother of Ahmad and Suha has sickle cell anemia. Hence, they have genotype Hb${}^S$Hb${}^S$. Since, their parents do not have sickle cell anemia but one of their son has, they are carrier of sickle cell disease. They have genotype Hb${}^S$Hb${}^A$. Therefore, Ahmad and Suha could be either carrier of the disease and have genotype Hb${}^S$Hb${}^A$ or have genotype Hb${}^A$Hb${}^A$.Hence, there are very little chances that their children will have sickle cell disease.

Thus, the correct answer is 'There is very little chance that any of their children will have sickle cell disease'.