b-Aminoisobutyric Acid (Urine)

- High b-Aminoisobutyric Acid in urine is a benign metabolic polymorphism present in some human populations due to deficiency of hepatic BAIB-pyruvate transaminase.

- Over 40% of some asian populations have this condition.

- Excretion of BAIB increases in x-ray radiation-induced destruction of DNA.

- Increased urinary concentrations of beta-aminoisobutyric acid were frequently found in tumour patients, especially in patients with leukaemia and non-Hodgkin lymphoma.

- Parenteral administration of excessive folic acid (by injection for example) also stimulates cell turnover that results in increased BAIB.

- If this amino acid is high, it may indicate a vitamin B6 deficiency.

- It has been observed that women excrete increased amounts of BAIB during pregnancy.

Although excretion of amino acids in the urine is frequently a symptom of a metabolic disorder, often genetic in nature, the excretion of high levels of BAIB does not appear to be causing harm or damage, but neither is its adaptive significance yet clear.

Beta-aminoisobutyric acid (BAIB) is an amino acid end product of the pyrimidine metabolism. It is excreted in small quantities into the urine in almost all human beings. Thymine, released when RNA and DNA are degraded, enters a catabolic pathway that leads to Beta-Aminoisobutyric Acid.