Question

The first clinical gene therapy was given for treating?
(a) Chickenpox
(b) Rheumatoid arthritis
(c) Adenosine deaminase deficiency
(d) Diabetes mellitus

Answer 1

Gene therapy is a revolutionized technique of genetic engineering where a gene defect is corrected by delivering a normal gene in place of the incorrect or missing one. The first clinical therapy was given for treating an immune deficiency disorder.

Complete step by step answer:
The first clinical gene therapy was performed in 1990 in a 4 years old girl who was battling with severe combined immunodeficiency disorder. It is due to the deficiency of an enzyme adenosine deaminase (ADA) that is crucial for the immune system to eliminate deoxyadenosine, a toxic molecule for lymphocytes. She received an infusion of white blood cells that had been genetically modified to contain the gene that was non- functional in her genome. But in this method of gene therapy, the patient required a periodic infusion of such genetically engineered lymphocytes.
- Chickenpox is a viral disease caused by the Varicella zoster virus. It is a type of infectious disease with rash- like blisters covering the face and in some extreme cases the whole body. The symptoms include painful red blisters followed by itching, extreme weakness, and at times breathing problems too. It can be prevented by a vaccine that has been proved effective worldwide. A total of 2 doses is required for its complete effectiveness.
- Rheumatoid arthritis is an autoimmune disorder where the immune cells attack the synovial membrane and thus leads to the inflammation of joints. This further leads to the disfigurement of the joints and their painful mobility. There’s no direct cure or medications prescribed but studies show that physiotherapy and some early modifying drugs can prevent its onset.
- Diabetes mellitus is a result of metabolic disorder wherein the blood glucose levels are on the rise due to the shortage of the hormone insulin. They are characterized by blurry vision, late healing of sores, dry itchy skin, and frequent urinary infections. They are cured by lifestyle changes, diet, and insulin therapy.
So, the correct answer is ‘(c) Adenosine deaminase deficiency.’

Note:
- Diabetes mellitus is of two types - type I and type II.
- In type I diabetes, the beta cells of the pancreas are damaged and thus are unable to produce any sufficient quantities of insulin that can be used by the body.
- In type II diabetes, the pancreas produces little insulin but the body cells are unable to use it. This leads to little or no utilization of glucose in the cells which causes its buildup in the blood.