This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:N-guanidinoacetate methyltransferase. Other names in common use include GA methylpherase, guanidinoacetate methyltransferase, guanidinoacetate transmethylase, methionine-guanidinoacetic transmethylase, and guanidoacetate methyltransferase. This enzyme participates in glycine, serine and threonine metabolism and arginine and proline metabolism.
The protein encoded by this gene is a methyltransferase that converts guanidoacetate to creatine, using S-adenosylmethionine as the methyl donor. Defects in this gene have been implicated in neurologic syndromes and muscular hypotonia, probably due to creatine deficiency and accumulation of guanidinoacetate in the brain of affected individuals. Two transcript variants encoding different isoforms have been described for this gene.
Morris AA, Appleton RE, Power B, et al. (2007). "Guanidinoacetate methyltransferase deficiency masquerading as a mitochondrial encephalopathy". J. Inherit. Metab. Dis. 30 (1): 100. doi:10.1007/s10545-006-0478-2. PMID17171576.
Almeida LS, Rosenberg EH, Martinez-Muñoz C, et al. (2007). "Overexpression of GAMT restores GAMT activity in primary GAMT-deficient fibroblasts". Mol. Genet. Metab. 89 (4): 392–4. doi:10.1016/j.ymgme.2006.06.006. PMID16899382.
Chae YJ, Chung CE, Kim BJ, et al. (1998). "The gene encoding guanidinoacetate methyltransferase (GAMT) maps to human chromosome 19 at band p13.3 and to mouse chromosome 10". Genomics. 49 (1): 162–4. doi:10.1006/geno.1998.5236. PMID9570966.