NORD gratefully acknowledges Brendan Lee, M.D., Ph.D., Robert and Janice McNair Endowed Chair in Molecular and Human Genetics, Professor and Chairman, Department of Molecular and Human Genetics, Baylor College of Medicine for assistance in the preparation of this report.
Synonyms of Argininosuccinic Aciduria
- Arginino succinase Deficiency
- Argininosuccinate Lyase Deficiency
- Argininosuccinate Acid Lyase Deficiency
- ASA Deficiency
- ASL Deficiency
Argininosuccinic aciduria is a rare genetic disorder characterized by deficiency or lack of the enzyme argininosuccinate lyase (ASL). This enzyme is one of six enzymes that play a role in the breakdown and removal of nitrogen from the body, a process known as the urea cycle. The lack of this argininosuccinate lyase results in excessive accumulation of nitrogen, in the form of ammonia (hyperammonemia), in the blood. Ammonia is a neurotoxin, which means that it damages or inhibits the function of neurons, the cells of the central nervous system. Excess ammonia travels to the central nervous system through the blood, resulting in the symptoms and physical findings associated with the disorder. Affected infants may experience vomiting, refusal to eat, progressive lethargy, and coma. Argininosuccinic aciduria is inherited as an autosomal recessive trait.
The urea cycle disorders are a group of rare disorders affecting the urea cycle, a series of biochemical processes in which nitrogen is converted into urea and removed from the body through the urine. Nitrogen is a waste product of protein metabolism. Failure to break down nitrogen results in the abnormal accumulation of nitrogen, in the form of ammonia, in the blood.
NORD Member Organizations
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