Serine hydroxymethyltransferase (SHMT) is an enzyme involved in amino acid metabolism, responsible for converting serine to glycine while generating 5,10-methylene tetrahydrofolate. The SHMT family includes two main isoforms: SHMT1 (cytosolic) and SHMT2 (mitochondrial). These enzymes are expressed in tissues such as the liver, kidneys, and cancer cells. SHMT plays a key role in regulating one-carbon metabolism, nucleotide synthesis, and cell proliferation. The specific expression and mutations of the gene are associated with various diseases, including cancer, cardiovascular diseases, and neurological disorders.