rs374059924

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2_SupportingPS3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_001482.3:c.622G>A variant in GATM is a missense variant that is predicted to result in the substitution of alanine by threonine at amino acid 208 (p.Ala208Thr). To our knowledge, this variant has not been reported in an individual with AGAT deficiency in the published literature. The highest population minor allele frequency for this variant in gnomAD v4.1.0. is 0.00002228 (1/44874 alleles) in the East Asian population, which is lower than the ClinGen CCDS VCEP’s threshold for PM2_Supporting (<0.000055), meeting this criterion (PM2_Supporting). When overexpressed in HeLa cells, the variant resulted in <15% of wild-type AGAT enzyme activity (PMID:27233232) (PS3_Supporting). The computational predictor REVEL gives a score of 0.48 which is neither above nor below the thresholds predicting a damaging (>0.644) or benign (<0.29) impact on AGAT function. SpliceAI predicts that the variant has no impact on splicing. There is a ClinVar entry for this variant (Variation ID: 225916). In summary, this variant meets the criteria to be classified as a variant of uncertain significance for AGAT deficiency. GATM-specific ACMG/AMP criteria applied, as specified by the ClinGen CCDS VCEP (Specifications Version 2.0.0.): PS3_Supporting, PM2_Supporting.(Classification approved by the ClinGen CCDS VCEP on April 11, 2025). LINK:https://erepo.genome.network/evrepo/ui/classification/CA7542887/MONDO:0012996/025

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000041 ( 0 hom. )

Consequence

GATM
NM_001482.3 missense

Scores

8
9
2

Clinical Significance

Uncertain significance reviewed by expert panel U:2

Conservation

PhyloP100: 7.48

Publications

2 publications found
Variant links:
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

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PS3
For more information check the summary or visit ClinGen Evidence Repository.
PM2
For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GATMNM_001482.3 linkc.622G>A p.Ala208Thr missense_variant Exon 4 of 9 ENST00000396659.8 NP_001473.1 P50440-1A0A140VK19

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
GATMENST00000396659.8 linkc.622G>A p.Ala208Thr missense_variant Exon 4 of 9 1 NM_001482.3 ENSP00000379895.3 P50440-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251368
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000410
AC:
6
AN:
1461832
Hom.:
0
Cov.:
31
AF XY:
0.00000275
AC XY:
2
AN XY:
727212
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.00
AC:
0
AN:
44716
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86248
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5752
European-Non Finnish (NFE)
AF:
0.00000450
AC:
5
AN:
1111998
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Arginine:glycine amidinotransferase deficiency Uncertain:2
Apr 11, 2025
ClinGen Cerebral Creatine Deficiency Syndromes Variant Curation Expert Panel, ClinGen
Significance:Uncertain significance
Review Status:reviewed by expert panel
Collection Method:curation

The NM_001482.3:c.622G>A variant in GATM is a missense variant that is predicted to result in the substitution of alanine by threonine at amino acid 208 (p.Ala208Thr). To our knowledge, this variant has not been reported in an individual with AGAT deficiency in the published literature. The highest population minor allele frequency for this variant in gnomAD v4.1.0. is 0.00002228 (1/44874 alleles) in the East Asian population, which is lower than the ClinGen CCDS VCEP’s threshold for PM2_Supporting (<0.000055), meeting this criterion (PM2_Supporting). When overexpressed in HeLa cells, the variant resulted in <15% of wild-type AGAT enzyme activity (PMID: 27233232) (PS3_Supporting). The computational predictor REVEL gives a score of 0.48 which is neither above nor below the thresholds predicting a damaging (>0.644) or benign (<0.29) impact on AGAT function. SpliceAI predicts that the variant has no impact on splicing. There is a ClinVar entry for this variant (Variation ID: 225916). In summary, this variant meets the criteria to be classified as a variant of uncertain significance for AGAT deficiency. GATM-specific ACMG/AMP criteria applied, as specified by the ClinGen CCDS VCEP (Specifications Version 2.0.0.): PS3_Supporting, PM2_Supporting. (Classification approved by the ClinGen CCDS VCEP on April 11, 2025). -

Jul 07, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Experimental studies have shown that this missense change affects GATM function (PMID: 27233232). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt GATM protein function. ClinVar contains an entry for this variant (Variation ID: 225916). This variant has not been reported in the literature in individuals affected with GATM-related conditions. This variant is present in population databases (rs374059924, gnomAD 0.006%). This sequence change replaces alanine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 208 of the GATM protein (p.Ala208Thr). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.65
BayesDel_addAF
Uncertain
0.036
T
BayesDel_noAF
Uncertain
-0.020
CADD
Pathogenic
30
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.73
D;.;.
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.81
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Pathogenic
0.98
D;D;D
M_CAP
Benign
0.048
D
MetaRNN
Pathogenic
0.82
D;D;D
MetaSVM
Uncertain
-0.22
T
MutationAssessor
Pathogenic
3.1
M;M;.
PhyloP100
7.5
PrimateAI
Uncertain
0.70
T
PROVEAN
Uncertain
-3.9
D;D;D
REVEL
Uncertain
0.48
Sift
Uncertain
0.0010
D;D;D
Sift4G
Uncertain
0.0060
D;D;.
Polyphen
1.0
D;D;.
Vest4
0.86
MVP
0.42
MPC
1.7
ClinPred
1.0
D
GERP RS
5.5
Varity_R
0.84
gMVP
0.90
Mutation Taster
=73/27
polymorphism

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

Publications

Other links and lift over

dbSNP: rs374059924; hg19: chr15-45660321; API