chr19-1398964-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate

The NM_000156.6(GAMT):​c.522G>T​(p.Trp174Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000031 in 1,613,322 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

GAMT
NM_000156.6 missense

Scores

9
9
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 5.81
Variant links:
Genes affected
GAMT (HGNC:4136): (guanidinoacetate N-methyltransferase) The protein encoded by this gene is a methyltransferase that converts guanidoacetate to creatine, using S-adenosylmethionine as the methyl donor. Defects in this gene have been implicated in neurologic syndromes and muscular hypotonia, probably due to creatine deficiency and accumulation of guanidinoacetate in the brain of affected individuals. Two transcript variants encoding different isoforms have been described for this gene. Pseudogenes of this gene are found on chromosomes 2 and 13. [provided by RefSeq, Feb 2012]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1
In a domain RMT2 (size 223) in uniprot entity GAMT_HUMAN there are 36 pathogenic changes around while only 7 benign (84%) in NM_000156.6
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.87

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
GAMTNM_000156.6 linkuse as main transcriptc.522G>T p.Trp174Cys missense_variant 5/6 ENST00000252288.8 NP_000147.1
GAMTNM_138924.3 linkuse as main transcriptc.522G>T p.Trp174Cys missense_variant 5/5 NP_620279.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
GAMTENST00000252288.8 linkuse as main transcriptc.522G>T p.Trp174Cys missense_variant 5/61 NM_000156.6 ENSP00000252288 P1Q14353-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152192
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461130
Hom.:
0
Cov.:
32
AF XY:
0.00000413
AC XY:
3
AN XY:
726870
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000180
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152192
Hom.:
0
Cov.:
32
AF XY:
0.0000135
AC XY:
1
AN XY:
74346
show subpopulations
Gnomad4 AFR
AF:
0.0000483
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.00
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.00000756

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsFeb 05, 2024The p.W174C variant (also known as c.522G>T), located in coding exon 5 of the GAMT gene, results from a G to T substitution at nucleotide position 522. The tryptophan at codon 174 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingCeGaT Center for Human Genetics TuebingenJul 01, 2023GAMT: PM2, PP3 -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.94
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.33
CADD
Pathogenic
32
DANN
Uncertain
0.99
DEOGEN2
Pathogenic
0.84
D;.;.
Eigen
Uncertain
0.60
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.95
D;D;D
M_CAP
Pathogenic
0.76
D
MetaRNN
Pathogenic
0.87
D;D;D
MetaSVM
Uncertain
0.58
D
MutationAssessor
Pathogenic
3.0
M;.;M
MutationTaster
Benign
1.0
D;D
PrimateAI
Uncertain
0.74
T
PROVEAN
Uncertain
-4.2
D;.;D
REVEL
Pathogenic
0.81
Sift
Uncertain
0.0050
D;.;D
Sift4G
Uncertain
0.046
D;.;D
Polyphen
1.0
D;.;.
Vest4
0.90
MutPred
0.61
Loss of ubiquitination at K179 (P = 0.0656);.;Loss of ubiquitination at K179 (P = 0.0656);
MVP
0.98
MPC
0.80
ClinPred
0.99
D
GERP RS
4.0
Varity_R
0.78
gMVP
0.94

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs370421531; hg19: chr19-1398963; COSMIC: COSV52038774; COSMIC: COSV52038774; API