2-Aminoisobutyric acid, also known as alpha-methylalanine or a-aminoisobutanoate, belongs to the class of organic compounds known as alpha amino acids. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). 2-Aminoisobutyric acid is a very hydrophobic molecule, practically insoluble (in water), and relatively neutral. 2-Aminoisobutyric acid exists in all living organisms, ranging from bacteria to humans. Outside of the human body, 2-Aminoisobutyric acid has been detected, but not quantified in, milk (cow). This could make 2-aminoisobutyric acid a potential biomarker for the consumption of these foods. Aminoisobutyric acid is a nonprotein amino acid (is an end product of pyrimidine metabolism) excreted in the urine of about 5% of healthy individuals , and high excretion is an autosomal recessive phenotype.