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ADA adenosine deaminase

Gene ID: 100, updated on 2-Mar-2024
Gene type: protein coding
Also known as: ADA1


This gene encodes an enzyme that catalyzes the hydrolysis of adenosine to inosine in the purine catabolic pathway. Various mutations have been described for this gene and have been linked to human diseases related to impaired immune function such as severe combined immunodeficiency disease (SCID) which is the result of a deficiency in the ADA enzyme. In ADA-deficient individuals there is a marked depletion of T, B, and NK lymphocytes, and consequently, a lack of both humoral and cellular immunity. Conversely, elevated levels of this enzyme are associated with congenital hemolytic anemia. [provided by RefSeq, Sep 2019]

Associated conditions

See all available tests in GTR for this gene

Host-microbe interactions have shaped the genetic architecture of inflammatory bowel disease.
GeneReviews: Not available
Severe combined immunodeficiency, autosomal recessive, T cell-negative, B cell-negative, NK cell-negative, due to adenosine deaminase deficiencySee labs

Genomic context

Chromosome: 20; NC_000020.11 (44619522..44651699, complement)
Total number of exons:


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