Answer: Adenosine deaminase.
- A Helicase
- B Phenylalanine hydroxylase
- C Amylase
- D Adenosine deaminase
Correct answer: D. Adenosine deaminase
Explanation: The 1990 gene therapy treated a girl with adenosine deaminase (ADA) deficiency, a disorder caused by a defective gene for this enzyme.
Concept context
GM crops, transgenic animals, gene therapy, molecular diagnostics, and bioethics. Frequent 2–3 mark questions in NEET.