NM_001482.3:c.1111dupA

Variant names:

• chr15-45363947-A-AT
• rs397515542
• NM_001482.3:c.1111dupA

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PP4_Strong PM2_Supporting PVS1_Strong PM3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_001482.3:c.1111dup (p.Met371AsnfsTer6) variant in GATM is a frameshift variant predicted to cause a premature stop codon in the last 50 nucleotides of the penultimate exon and therefore to escape nonsense mediated decay. More than 10% of the protein is predicted to be removed (PVS1_Strong). This variant has been detected in two siblings with AGAT deficiency who had significantly decreased creatine peak on brain MRS (PMID 20682460) (PP4_Strong). Both individuals were homozygous for the variant, confirmed in trans by parental testing (PMID 20682460) (PM3_Supporting). This variant is absent from gnomAD v2.1.1 (PM2_Supporting). In summary, this variant meets the criteria to be classified as pathogenic for AGAT deficiency based on the ACMG/AMP criteria applied, as specified by the ClinGen Cerebral Creatine Deficiency Syndromes Variant Curation Expert Panel (Specifications Version 1.1.0): PVS1_Strong, PP4_Strong, PM3_Supporting, PM2_Supporting.(Classification approved by the ClinGen CCDS VCEP on June 6, 2022). LINK:https://erepo.genome.network/evrepo/ui/classification/CA344713/MONDO:0012996/025

• Frequency: Genomes: not found (cov: 32)
• Consequence: GATM NM_001482.3 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:2 O:1
• Conservation: PhyloP100: 5.79
• Publications: 4 publications found

Genes affected

GATM (HGNC:4175): (glycine amidinotransferase) This gene encodes a mitochondrial enzyme that belongs to the amidinotransferase family. This enzyme is involved in creatine biosynthesis, whereby it catalyzes the transfer of a guanido group from L-arginine to glycine, resulting in guanidinoacetic acid, the immediate precursor of creatine. Mutations in this gene cause arginine:glycine amidinotransferase deficiency, an inborn error of creatine synthesis characterized by cognitive disability, language impairment, and behavioral disorders. [provided by RefSeq, Jul 2008]

GATM Gene-Disease associations (from GenCC):

• AGAT deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Orphanet, Ambry Genetics, G2P
• Fanconi renotubular syndrome 1

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics
• primary Fanconi syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM3: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001482.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GATM	NM_001482.3	MANE Select	c.1111dupA	p.Met371AsnfsTer6	frameshift	Exon 8 of 9	NP_001473.1
	GATM	NM_001321015.2		c.724dupA	p.Met242AsnfsTer6	frameshift	Exon 11 of 12	NP_001307944.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GATM	ENST00000396659.8	TSL:1 MANE Select	c.1111dupA	p.Met371AsnfsTer6	frameshift	Exon 8 of 9	ENSP00000379895.3
	GATM	ENST00000558362.5	TSL:1	n.2767dupA		non_coding_transcript_exon	Exon 7 of 8
	GATM	ENST00000675701.1		c.1051dupA	p.Met351AsnfsTer6	frameshift	Exon 8 of 9	ENSP00000502671.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

Arginine:glycine amidinotransferase deficiency Pathogenic:2 Other:1

Jun 06, 2022

ClinGen Cerebral Creatine Deficiency Syndromes Variant Curation Expert Panel, ClinGen

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The NM_001482.3:c.1111dup (p.Met371AsnfsTer6) variant in GATM is a frameshift variant predicted to cause a premature stop codon in the last 50 nucleotides of the penultimate exon and therefore to escape nonsense mediated decay. More than 10% of the protein is predicted to be removed (PVS1_Strong). This variant has been detected in two siblings with AGAT deficiency who had significantly decreased creatine peak on brain MRS (PMID 20682460) (PP4_Strong). Both individuals were homozygous for the variant, confirmed in trans by parental testing (PMID 20682460) (PM3_Supporting). This variant is absent from gnomAD v2.1.1 (PM2_Supporting). In summary, this variant meets the criteria to be classified as pathogenic for AGAT deficiency based on the ACMG/AMP criteria applied, as specified by the ClinGen Cerebral Creatine Deficiency Syndromes Variant Curation Expert Panel (Specifications Version 1.1.0): PVS1_Strong, PP4_Strong, PM3_Supporting, PM2_Supporting. (Classification approved by the ClinGen CCDS VCEP on June 6, 2022).

Oct 01, 2010

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

GeneReviews

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		5.8
Mutation Taster		=1/199	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs397515542; hg19: chr15-45656145;