Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): In gene therapy for ADA deficiency, the patient requires periodic infusion of genetically engineered lymphocytes. Reason (R): The genetically engineered lymphocytes introduced into the patient's body are immortal and continue to divide indefinitely. In the light of the above statements, choose the

Step-by-step solution

Assertion (A) is true because in gene therapy for ADA deficiency, lymphocytes from the blood of the patient are grown in a culture outside the body, engineered to contain a functional ADA cDNA, and then returned to the patient. Because these cells are not immortal, the patient requires periodic infusion of such genetically engineered lymphocytes. Reason (R) is false because somatic cells like lymphocytes have a definite life span and are not immortal. This lack of immortality is precisely the reason why periodic in