ACMG Statements and Guidelines
These online statements and guidelines are definitive and may be cited using the digital object identifier (DOI). These recommendations are designed primarily as an educational resource for medical geneticists and other healthcare providers to help them provide quality medical genetics services; they should not be considered inclusive of all proper procedures and tests or exclusive of other procedures and tests that are reasonably directed to obtaining the same results. Please refer to the leading disclaimer in each document for more information.
- Amino acid abnormalities are observed in a broad spectrum of inheritedmetabolic diseases, such as disorders of amino acid metabolism and transport,organic acidemias, and ureagenesis defects. Comprehensive analysis of physiologicamino acids in blood, urine, and cerebrospinal fluid is typically performed in thefollowing clinical settings: evaluation of symptomatic patients in whom a diagnosisis not known; evaluation of previously diagnosed patients to monitor treatmentefficacy; evaluation of asymptomatic or presymptomatic (at-risk) relatives of knownpatients; follow-up testing for an abnormal newborn screen; and assessment ofdietary protein adequacy or renal function in general patient populations.Currently, the most common analytical method to quantify amino acids is based on ionexchange chromatography using post-column derivatization with ninhydrin andspectrophotometric detection.
- Determination of plasma amino acid levels has become a key piece of information in the diagnosis and clinical management of a group of metabolic genetic disorders. Appropriate laboratory methodologies have been published for amino acid analysis, yet there is a need for direction for the laboratory in performing this testing. The following guidelines were generated by a working group of the American College of Medical Genetics Laboratory Quality Assurance Committee. Based upon a body of knowledge and professional experience, these guidelines and standards are to be the benchmark for performance of amino acid analysis for clinical interpretation.