15-45368137-T-C

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2PM5PP3_ModeratePP5_Moderate

The NM_001482.3(GATM):​c.608A>G​(p.Tyr203Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,858 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Y203S) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

GATM
NM_001482.3 missense

Scores

12
5
2

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 7.58

Publications

5 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: Likely_pathogenic. The variant received 8 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr15-45368137-T-G is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 55921.Status of the report is reviewed_by_expert_panel, 3 stars.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.923
PP5
Variant 15-45368137-T-C is Pathogenic according to our data. Variant chr15-45368137-T-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 3716750.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
GATMNM_001482.3 linkc.608A>G p.Tyr203Cys 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.608A>G p.Tyr203Cys missense_variant Exon 4 of 9 1 NM_001482.3 ENSP00000379895.3 P50440-1

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461858
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727230
show subpopulations
⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5750
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112002
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Likely pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Arginine:glycine amidinotransferase deficiency Pathogenic:1
Oct 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 203 of the GATM protein (p.Tyr203Cys). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with GATM-related conditions. Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt GATM protein function with a positive predictive value of 95%. This variant disrupts the p.Tyr203 amino acid residue in GATM. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 23770102, 27233232). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.37
BayesDel_addAF
Pathogenic
0.31
D
BayesDel_noAF
Pathogenic
0.21
CADD
Pathogenic
29
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.80
D;.;.
Eigen
Pathogenic
0.81
Eigen_PC
Pathogenic
0.76
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.93
D;D;D
M_CAP
Uncertain
0.18
D
MetaRNN
Pathogenic
0.92
D;D;D
MetaSVM
Benign
-0.36
T
MutationAssessor
Pathogenic
3.3
M;M;.
PhyloP100
7.6
PrimateAI
Uncertain
0.71
T
PROVEAN
Pathogenic
-9.0
D;D;D
REVEL
Pathogenic
0.65
Sift
Pathogenic
0.0
D;D;D
Sift4G
Pathogenic
0.0
D;D;.
Polyphen
1.0
D;D;.
Vest4
0.96
MutPred
0.77
Loss of MoRF binding (P = 0.0907);Loss of MoRF binding (P = 0.0907);.;
MVP
0.58
MPC
1.9
ClinPred
1.0
D
GERP RS
4.5
Varity_R
0.94
gMVP
0.97

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: rs397514709; hg19: chr15-45660335; COSMIC: COSV67540716; COSMIC: COSV67540716; API