If both parents are sickle cell anemia patients then the likelyhood of off springs having the disease is
**Core Concept**
Sickle cell anemia is an autosomal recessive genetic disorder caused by a mutation in the HBB gene, leading to abnormal hemoglobin production. Understanding the genetic inheritance of this condition is crucial for predicting the likelihood of offspring being affected.
**Why the Correct Answer is Right**
In autosomal recessive disorders, an individual must inherit two copies of the mutated gene (one from each parent) to express the disease. Parents who are both carriers of the mutated gene have a 25% chance of passing it to each child, resulting in affected offspring. This is because each child has a 50% chance of inheriting the mutated gene from each parent, and the combination of two mutated genes leads to the expression of the disease.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is likely incorrect because it does not account for the autosomal recessive inheritance pattern of sickle cell anemia.
**Option B:** This option is incorrect because it does not accurately represent the probability of offspring inheriting the disease when both parents are carriers.
**Option C:** This option is incorrect because it implies a different mode of inheritance or probability that is not consistent with autosomal recessive disorders.
**Clinical Pearl / High-Yield Fact**
It is essential to remember that autosomal recessive disorders, like sickle cell anemia, often have a higher prevalence in populations with a high frequency of the mutated gene. This is because the disease is more likely to be expressed when two carriers have children.
**Correct Answer: D. 25%**