The technology used in research of in-born errors of metabolism disorders has changed drastically from EIA, RIA, FIA, ELISA to LC and tandem MS for the past 50 years. The research areas include metabolic, genetic and endocrine
disorders. The current focus of research activities varies worldwide due to demographics and ethnic background, including amino acid disorders, fatty acid oxidation disorders, endocrinopathies, lysosomal storage disorders and others.