NM_001482.3:c.1037C>T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. BP4PM2_SupportingPS3_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_001482.3:c.1037C>T variant in GATM is a missense variant predicted to cause substitution of proline by leucine at amino acid 346 (p.Pro346Leu). To our knowledge, this variant has not been reported in the literature in any individuals with AGAT deficiency. The highest population minor allele frequency in gnomAD v4.1.0. is 0.000002545 (3/1178764 alleles) in the non-Finnish European population, which is lower than the ClinGen CCDS VCEP’s threshold for PM2_Supporting (<0.000055), meeting this criterion (PM2_Supporting). Expression of the variant in HeLa cells resulted in <10% wild type AGAT activity indicating that this variant may impact protein function (PMID 27233232)(PS3_Supporting). The computational predictor REVEL gives a score of 0.237 which is below the threshold of 0.29, evidence that does not predict a damaging effect on AGAT function (PMID:36413997), and SpliceAI predicts that the variant has no impact on splicing (BP4). In summary, this variant meets the criteria to be classified as uncertain significance 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 2.0.0): PM2_Supporting, PS3_Supporting, BP4.(Classification approved by the ClinGen CCDS VCEP on April 11, 2025). LINK:https://erepo.genome.network/evrepo/ui/classification/CA270166553/MONDO:0012996/025

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

GATM
NM_001482.3 missense

Scores

4
7
8

Clinical Significance

Uncertain significance reviewed by expert panel U:3

Conservation

PhyloP100: 8.33

Publications

1 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 1 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.
BP4
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.1037C>T p.Pro346Leu missense_variant Exon 7 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.1037C>T p.Pro346Leu missense_variant Exon 7 of 9 1 NM_001482.3 ENSP00000379895.3 P50440-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152092
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251396
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000137
AC:
2
AN:
1460414
Hom.:
0
Cov.:
29
AF XY:
0.00000138
AC XY:
1
AN XY:
726626
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33450
American (AMR)
AF:
0.00
AC:
0
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26118
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39670
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86220
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53394
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.00000180
AC:
2
AN:
1110744
Other (OTH)
AF:
0.00
AC:
0
AN:
60334
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
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
AF:
0.00000657
AC:
1
AN:
152092
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74296
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41406
American (AMR)
AF:
0.00
AC:
0
AN:
15272
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5192
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4820
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10596
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.0000468
Hom.:
0
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
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.1037C>T variant in GATM is a missense variant predicted to cause substitution of proline by leucine at amino acid 346 (p.Pro346Leu). To our knowledge, this variant has not been reported in the literature in any individuals with AGAT deficiency. The highest population minor allele frequency in gnomAD v4.1.0. is 0.000002545 (3/1178764 alleles) in the non-Finnish European population, which is lower than the ClinGen CCDS VCEP’s threshold for PM2_Supporting (<0.000055), meeting this criterion (PM2_Supporting). Expression of the variant in HeLa cells resulted in <10% wild type AGAT activity indicating that this variant may impact protein function (PMID 27233232)(PS3_Supporting). The computational predictor REVEL gives a score of 0.237 which is below the threshold of 0.29, evidence that does not predict a damaging effect on AGAT function (PMID: 36413997), and SpliceAI predicts that the variant has no impact on splicing (BP4). In summary, this variant meets the criteria to be classified as uncertain significance 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 2.0.0): PM2_Supporting, PS3_Supporting, BP4. (Classification approved by the ClinGen CCDS VCEP on April 11, 2025). -

Aug 31, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 346 of the GATM protein (p.Pro346Leu). This variant is present in population databases (rs142814307, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with GATM-related conditions. ClinVar contains an entry for this variant (Variation ID: 225920). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). Experimental studies have shown that this missense change affects GATM function (PMID: 27233232). 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. -

not specified Uncertain:1
Apr 04, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: GATM c.1037C>T (p.Pro346Leu) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251396 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.1037C>T in individuals affected with Arginine:glycine Amidinotransferase Deficiency has been reported. At least one publication reports experimental evidence evaluating an impact on protein function and this variant affected the GATM protein function (DesRoches_2016). The following publication have been ascertained in the context of this evaluation (PMID: 27233232). ClinVar contains an entry for this variant (Variation ID: 225920). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.33
BayesDel_addAF
Uncertain
0.036
T
BayesDel_noAF
Benign
-0.19
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.84
D;.
Eigen
Uncertain
0.55
Eigen_PC
Uncertain
0.59
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D;D
M_CAP
Benign
0.026
D
MetaRNN
Pathogenic
0.78
D;D
MetaSVM
Benign
-0.86
T
MutationAssessor
Uncertain
2.3
M;M
PhyloP100
8.3
PrimateAI
Uncertain
0.67
T
PROVEAN
Uncertain
-3.7
D;D
REVEL
Benign
0.24
Sift
Benign
0.044
D;D
Sift4G
Benign
0.18
T;T
Polyphen
0.95
P;P
Vest4
0.78
MVP
0.24
MPC
0.81
ClinPred
0.96
D
GERP RS
5.4
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.49
gMVP
0.85

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: rs142814307; hg19: chr15-45657000; API