During gene therapy, which vector is used to introduce functional ADA cDNA into lymphocyte ?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Retrovirus
Gene therapy corrects a gene defect by putting a normal gene into a patient’s cells. The first clinical gene therapy, in 1990, treated a 4-year-old girl with ADA (adenosine deaminase) deficiency.
Option (4) Retrovirus — Correct. The patient’s lymphocytes are grown outside the body, and functional ADA cDNA is put into them using a retroviral vector, that is, a retrovirus used as the vector. The cells are then returned to the patient.
NCERT Extract:
Gene Therapy – “… As a first step towards gene therapy, lymphocytes from the blood of the patient are grown in a culture outside the body. A functional ADA cDNA (using a retroviral vector) is then introduced into these lymphocytes, which are subsequently returned to the patient.”