- A Cystic fibrosis, a disease which is caused by a defective CFTR chloride channel gene on chromosome 7 specifically
- B Adenosine deaminase deficiency (causing severe combined immunodeficiency) by introducing functional ADA gene into T cells
- C Hemophilia A, a disease which is caused by a deficiency of blood clotting factor VIII in blood plasma specifically
- D Sickle cell disease, a condition which is caused by a single point mutation in the beta-globin gene specifically
Correct answer: B. Adenosine deaminase deficiency (causing severe combined immunodeficiency) by introducing functional ADA gene into T cells
Explanation: First approved gene therapy (1990, Blaese/Anderson): ADA-SCID. T cells from patient transduced with retroviral vector containing ADA gene. Restored immune function in multiple patients.
Concept context
GM crops, transgenic animals, gene therapy, molecular diagnostics, and bioethics. Frequent 2–3 mark questions in NEET.