Master Adenosine Deaminase Deficiency with Picmonic for Medicine

Adenosine deaminase deficiency is an autosomal recessive metabolic disorder that is one of the major causes of severe combined immunodeficiency (SCID). Adenosine deaminase is an enzyme involved in purine metabolism. It is used to break down adenosine to inosine for the turnover of nucleic acids for DNA synthesis and cell growth. This deficiency leads to an accumulation of deoxyadenosine which leads to a buildup of ATP. High ATP, which normally activates RNR, leads to high dATP, which inactivates the enzyme ribonucleotide reductase, which is a key enzyme in DNA synthesis. This in turn prevents DNA synthesis. Because developing T cells and B cells are extremely mitotically active, these cells are susceptible to cell death. Loss of B and T cell function causes severe immunodeficiency.