19-1397378-G-A

Position:

chr19-1397378-G-A

Variant summary

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

The NM_000156.6(GAMT):c.692C>T(p.Pro231Leu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,612,156 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 (★). Synonymous variant affecting the same amino acid position (i.e. P231P) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000014 ( 0 hom. )

Consequence

GAMT
NM_000156.6 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 9.57

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 links:

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 69 pathogenic changes around while only 17 benign (80%) in NM_000156.6

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.864

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
GAMT	NM_000156.6 linkuse as main transcript	c.692C>T	p.Pro231Leu	missense_variant	6/6	ENST00000252288.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
GAMT	ENST00000252288.8 linkuse as main transcript	c.692C>T	p.Pro231Leu	missense_variant	6/6	1	NM_000156.6	P1	Q14353-1
GAMT	ENST00000640762.1 linkuse as main transcript	c.623C>T	p.Pro208Leu	missense_variant	6/6	5
GAMT	ENST00000640164.1 linkuse as main transcript			downstream_gene_variant		2

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152218

Hom.:

Cov.:

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

GnomAD4 exome

AF:

0.00000137

AC:

AN:

1459938

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726298

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:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

8.99e-7

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152218

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74354

show subpopulations

Gnomad4 AFR

AF:

0.00

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:

0.0000147

Gnomad4 OTH

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Cerebral creatine deficiency syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 19, 2021

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. 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: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals affected with GAMT-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.007%). This sequence change replaces proline, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 231 of the GAMT protein (p.Pro231Leu). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.76

BayesDel_addAF

Pathogenic

0.45

BayesDel_noAF

Pathogenic

0.40

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Pathogenic

0.87

D;.

Eigen

Pathogenic

0.86

Eigen_PC

Pathogenic

0.81

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Benign

0.84

T;T

M_CAP

Uncertain

0.28

MetaRNN

Pathogenic

0.86

D;D

MetaSVM

Pathogenic

0.82

MutationAssessor

Uncertain

2.9

M;.

MutationTaster

Benign

1.0

PROVEAN

Pathogenic

-4.6

D;.

REVEL

Pathogenic

0.88

Sift

Uncertain

0.012

D;.

Sift4G

Pathogenic

0.0

D;.

Polyphen

1.0

D;.

Vest4

0.90

MutPred

0.51

Loss of disorder (P = 0.0514);.;

MVP

0.98

ClinPred

1.0

GERP RS

5.1

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.80

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over