VARSValyl-tRNA synthetase is an enzyme that in humans is encoded by the VARS gene.Functions catalyze the aminoacylation of tRNA by their cognate amino acid. Because of their central role in linking amino acids with nucleotide triplets contained in tRNAs, aminoacyl-tRNA synthetases are thought to be among the first proteins that appeared in evolution. The protein encoded by this gene belongs to class I aminoacyl-tRNA synthetase family and is located in the MHC [class III|class III region] of the major [histocompatibility complex].