BioBeyond – Disease Detective Practice Exam

Malik's chances of inheriting sickle cell disease depend on the genetic makeup of his parents. Sickle cell disease is a recessive condition caused by mutations in the hemoglobin gene. For a child to inherit the disease, they must receive two copies of the mutated gene, one from each parent.

If Malik's parents are carriers of the sickle cell trait (meaning they each have one normal hemoglobin gene and one mutated gene), each child they have would have a 25% chance of inheriting two mutated genes (which would result in sickle cell disease), a 50% chance of inheriting one mutated gene (making them a carrier), and a 25% chance of inheriting two normal genes (not being affected or a carrier).

Given this scenario, saying Malik has a 50% chance means he has that probability of being a carrier if both parents are carriers, but not inheriting the disease itself, which would only be 25%. Therefore, if the correct answer is stated as 50%, it indicates Malik has these potential genetic outcomes based on his parents' genotypes. Understanding inheritance in terms of dominant and recessive traits is crucial in determining sickle cell disease risks.