Question

Which one of the following is an autosomal dominant disorder?

• A. Myotonic dystrophy
• B. Phenylketonuria
• C. Hemophilia
• D. Thalassemia

Hint:

- Autosomal dominant → Huntington’s, Myotonic dystrophy - Autosomal recessive → PKU, Thalassemia - X-linked → Hemophilia

Answer 1

The Correct Option is A

Concept: Genetic disorders can be classified based on inheritance pattern:
• Autosomal dominant → Only one copy of mutant gene needed
• Autosomal recessive → Two copies needed
• X-linked → Linked to sex chromosomes

Step 1: Analyze each disorder.

• Myotonic dystrophy → Autosomal dominant (correct)
• Phenylketonuria → Autosomal recessive
• Hemophilia → X-linked recessive
• Thalassemia → Autosomal recessive

Step 2: Final conclusion.
Thus, the autosomal dominant disorder is: \[ Myotonic dystrophy \]