Specifically, ADA catalyzes the irreversible deamination of adenosine and deoxyadenosine to inosine and deoxyinosine (Zavialov and Engstrom, 2005). The enzyme adenosine deaminase functions as a catalyst in the deamination of adenosine and deoxyadenosine. Fig 11.8 from Janeway et al., 2005.Īdenosine deaminase deficiency resulting in severe combined immunodeficiency (ADA/SCID) in humans is characterized by a severely compromised immune system and a lack of functional T and B lymphocytes in affected individuals. Table 1 lists several of the common causes of severe combined immune deficiency, as well as the immune defect that they generate and the type of immune susceptibility that affected individuals experience. In fact, adenosine deaminase deficiency is the most common form of autosomally inherited SCID (Janeway et al., 2005). Another common cause of SCID is adenosine deaminase (ADA) deficiency approximately 20% of the SCID conditions diagnosed are the result of ADA deficiency (Carlucci et al., 2004). The most common form of SCID is X-linked SCID, which is caused by a deficiency of the IL2 receptor. There are numerous defects that result in the SCID phenotype and several of the most common causes are listed in Table 1. Severe combined immunodeficiency is associated with recurring opportunistic infections and often results in death at a young age (Blaese et al., 1995).

All forms of SCID are inherited (Kniffin, 2004). Severe combined immunodeficiency (SCID) is a human disorder characterized by defective T-cell function (Janeway, 2005). ***DISCLAIMER: This website is not intended to be used for medical advice or treatment.*** This web page was produced as an assignment for an undergraduate course at Davidson College.

What chromosome occurs with scid