Question

Who was the first patient who was given gene therapy? Why was the given treatment recurrent in nature?

Answer 1

First patient to be given gene therapy :

• The first patient who was given gene therapy was a 4 - year old girl in 1990.
• She was suffering from Severe Combined Immuno deficiency syndrome caused by a mutation in gene encoding for the enzyme adenosine deaminase (ADA).
• These patients have non-functional lymphocytes and they cannot mount immune responses against invading pathogens.
• Hence she was given gene therapy for ADA deficiency.

Treatment method :

Following is the treatment method:

• Lymphocytes from the patient’s blood were isolated.
• A functional ADA cDNA was introduced into them using a retroviral vector.
• Genetically engineered lymphocytes are then infused back into the patient’s blood.
• Now the lymphocytes could produce ADA.
• Since these lymphocytes are taken from the same patient, there was no sign of rejection.

Limitation of the gene therapy method for ADA :

• Lymphocytes with ADA cDNA infused periodically as this is not a permanent method to cure SCID, as lymphocytes are mortal cells.
• If gene therapy is performed at the early embryonic stages using bone marrow cells, it can be permanently cured..