The 5′-flanking region of the gene lacks typical TATAA sequence but has a single defined transcription initiation site detected by the primer extension method.

Several dimeric interactions are observed among the residues on the N-terminal loop, on α-helix D, and the flank on either side of β-strand 8 of the two monomers.

[8] The protein encoded by AMT catalyzes the release of ammonia and the transfer of a methylene carbon unit to a tetrahydrofolate moiety.

[11] The neonatal form manifests in the first hours to days of life with progressive lethargy, hypotonia, and myoclonic jerks leading to apnea and often death.

[12][13] Enzymatic confirmation of the diagnosis relies on measurement of glycine cleavage system (GCS) enzyme activity in liver obtained by open biopsy or autopsy.