19-1399013-C-T

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1PM2

The NM_000156.6(GAMT):​c.473G>A​(p.Arg158His) variant causes a missense change. The variant allele was found at a frequency of 0.000031 in 1,613,328 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R158S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000033 ( 0 hom. )

Consequence

GAMT
NM_000156.6 missense

Scores

4
13
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 5.70

Publications

2 publications found
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]
GAMT Gene-Disease associations (from GenCC):
  • guanidinoacetate methyltransferase deficiency
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P, ClinGen, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM1
In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 13 uncertain in NM_000156.6
PM2
Very rare variant in population databases, with high coverage;

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000156.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GAMT
NM_000156.6
MANE Select
c.473G>Ap.Arg158His
missense
Exon 5 of 6NP_000147.1Q14353-1
GAMT
NM_138924.3
c.473G>Ap.Arg158His
missense
Exon 5 of 5NP_620279.1Q14353-2

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
GAMT
ENST00000252288.8
TSL:1 MANE Select
c.473G>Ap.Arg158His
missense
Exon 5 of 6ENSP00000252288.1Q14353-1
GAMT
ENST00000902474.1
c.743G>Ap.Arg248His
missense
Exon 5 of 6ENSP00000572533.1
GAMT
ENST00000447102.8
TSL:2
c.473G>Ap.Arg158His
missense
Exon 5 of 5ENSP00000403536.2Q14353-2

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152206
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0000241
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:
0.0000160
AC:
4
AN:
250770
AF XY:
0.0000147
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000579
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000329
AC:
48
AN:
1461122
Hom.:
0
Cov.:
32
AF XY:
0.0000316
AC XY:
23
AN XY:
726852
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44718
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000348
AC:
3
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52718
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000387
AC:
43
AN:
1111966
Other (OTH)
AF:
0.00
AC:
0
AN:
60382
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
Heterozygous variant carriers
0
3
7
10
14
17
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:
0.0000131
AC:
2
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74366
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41450
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10630
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2086
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.450
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000712
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.00000824
AC:
1

ClinVar

ClinVar submissions
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
2
-
Deficiency of guanidinoacetate methyltransferase (2)
-
1
-
Cerebral creatine deficiency syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.15
BayesDel_addAF
Uncertain
0.083
D
BayesDel_noAF
Uncertain
-0.020
CADD
Pathogenic
32
DANN
Pathogenic
1.0
DEOGEN2
Pathogenic
0.84
D
Eigen
Uncertain
0.43
Eigen_PC
Uncertain
0.31
FATHMM_MKL
Uncertain
0.96
D
LIST_S2
Uncertain
0.95
D
M_CAP
Pathogenic
0.60
D
MetaRNN
Uncertain
0.65
D
MetaSVM
Uncertain
0.65
D
MutationAssessor
Pathogenic
2.9
M
PhyloP100
5.7
PrimateAI
Uncertain
0.52
T
PROVEAN
Uncertain
-2.8
D
REVEL
Uncertain
0.57
Sift
Uncertain
0.0070
D
Sift4G
Uncertain
0.029
D
Polyphen
1.0
D
Vest4
0.68
MutPred
0.39
Gain of ubiquitination at K161 (P = 0.0495)
MVP
0.94
MPC
0.71
ClinPred
0.97
D
GERP RS
1.9
Varity_R
0.49
gMVP
0.88
Mutation Taster
=52/48
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: rs750195151; hg19: chr19-1399012; COSMIC: COSV52041001; COSMIC: COSV52041001; API