The person is suffering from a hereditary disease called SCID (Severe Combined Immuno-deficiency Disease). It is caused due to defect in the gene for enzyme adenosine deaminase (ADA deficiency).

The person can be cured through gene therapy. Gene therapy is the technique of genetic engineering to replace faulty genes by a normal healthy functional genes. In gene therapy, genetically engineered lymphocytes are introduced into an ADA deficient patient. But as these cells do not always remain alive, the patient requires periodic infusion of such genetically engineered lymphocytes. However, if the isolated gene from bone narrow cells producing ADA is introduced into cells at early embryonic stages, it can be permanently cured.