J Pediatr Genet 2018; 07(03): 097-102
DOI: 10.1055/s-0038-1667036
Original Article
Georg Thieme Verlag KG Stuttgart · New York

Identification of Two Novel Mutations in Aminomethyltransferase Gene in Cases of Glycine Encephalopathy

Akella Radha Rama Devi
1   Department of Biochemical Genetics, Sandor Lifesciences Pvt. Ltd., Banjara Hills, Hyderabad, Telangana, India
2   Neuro-Metabolic Unit, Rainbow Children's Hospital, Hyderabad, Telangana, India
Lokesh Lingappa
2   Neuro-Metabolic Unit, Rainbow Children's Hospital, Hyderabad, Telangana, India
Shaik Mohammad Naushad
1   Department of Biochemical Genetics, Sandor Lifesciences Pvt. Ltd., Banjara Hills, Hyderabad, Telangana, India
› Author Affiliations
Further Information

Publication History

10 May 2018

04 June 2018

Publication Date:
06 July 2018 (online)


In this study, we report three cases of nonketotic hyperglycinemia (NKHG) diagnosed biochemically and molecularly. Clinical exome analysis in two families revealed two novel mutations in the aminomethyltransferase (AMT) gene, that is, c.14_15insT (p.Ser6LysfsTer22) and c.259–2A > T, both of them adversely affecting the protein. This is the first report of AMT gene mutations in NKHG from India. Prenatal diagnosis in the first family showed an unaffected fetus in the third pregnancy. The role of AMT protein is pivotal for the synthesis of 5,10-methylene tetrahydrofolate, the first metabolite in one-carbon metabolism that regulates DNA synthesis, repair, and methylation.

Supplementary Material

  • References

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