Question

Which of the following is a recessive genetic disorder?

• A. Huntington's disease
• B. Sickle cell anemia
• C. Achondroplasia
• D. Marfan syndrome

Hint:

If a question lists common genetic diseases, remember that Sickle Cell, Cystic Fibrosis, and Phenylketonuria (PKU) are classic examples of autosomal recessive inheritance.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Genetic disorders are classified as dominant or recessive based on whether one or two copies of the mutated gene are required for the disease to manifest.
Step 2: Detailed Explanation:
- Sickle cell anemia is an autosomal recessive disorder. This means an individual must inherit two copies of the mutated hemoglobin gene (HbS) to have the disease. Carriers (HbAS) usually do not show symptoms.
- Huntington's disease (Option A) is an autosomal dominant neurodegenerative disorder.
- Achondroplasia (Option C), a common form of dwarfism, is an autosomal dominant condition.
- Marfan syndrome (Option D), which affects connective tissue, is also an autosomal dominant disorder.
Step 3: Final Answer:
Sickle cell anemia is the recessive disorder among the choices provided.