Anti-Thymidine Kinase 2 antibodies are used for the immunodetection of the protein encoded by the TK2 gene. In humans, the canonical protein has a reported length of 265 amino acid residues and a mass of 31 kDa. Its subcellular localization is in the mitochondria. Alternative splicing is reported to yield 6 different isoforms for this protein. It is reported to be highly expressed in the liver, pancreas, muscle, and brain. A member of the DCK/DGK protein family, it is known to be involved with protein phosphorylation. The gene encoding this protein is implicated in Mitochondrial DNA depletion syndrome. Other names for this target antigen include MTTK, PEOB3, SCA31, TK2-EXT, thymidine kinase 2, mitochondrial, and MTDPS2. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.