Gene Therapy for Immunodeficiency Due to Adenosine Deaminase Deficiency

Deficiency of adenosine deaminase (ADA) causes a form of severe combined immunodeficiency disease. This study shows that gene therapy in the form of hematopoietic stem cells transduced with a viral vector containing the human ADA gene can restore immune function in patients with this disease. Deficiency of adenosine deaminase causes a form of severe combined immunodeficiency disease. This study shows that gene therapy can restore immune function in patients with the disease. Adenosine deaminase (ADA) deficiency is a fatal autosomal recessive form of severe combined immunodeficiency (SCID), of which failure to thrive, impaired immune responses, and recurrent infections are characteristics. 1 , 2 Toxic levels of purine metabolites (adenosine and adenine deoxyribonucleotides) due to the deficiency of ADA can cause hepatic, skeletal, neurologic, and behavioral alterations 1 , 3 , 4 and sensorineural deafness. 5 A hematopoietic stem-cell transplant from an HLA-identical sibling, the treatment of choice, is available for only a minority of patients 6 – 8 ; the use of alternative donors is associated with a high risk of death or lack of engraftment. 1 , 6 Administration of polyethylene . . .