19-1399548-T-C

Variant names:

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 2P and 1B. PM2BP4

The NM_138924.3(GAMT):c.367A>G(p.Thr123Ala) variant causes a missense change. The variant allele was found at a frequency of 0.0000453 in 1,612,676 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. T123T) has been classified as Likely benign.

Frequency

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

Exomes 𝑓: 0.000049 ( 0 hom. )

Consequence

GAMT
NM_138924.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 4.92

Publications

1 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: Orphanet, G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics

GAMT links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.29102075).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_138924.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	GAMT	NM_000156.6	MANE Select	c.367A>G	p.Thr123Ala	missense	Exon 3 of 6	NP_000147.1
	GAMT	NM_138924.3		c.367A>G	p.Thr123Ala	missense	Exon 3 of 5	NP_620279.1

Ensembl Transcripts

Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein
GAMT	ENST00000252288.8	TSL:1 MANE Select	c.367A>G	p.Thr123Ala	missense	Exon 3 of 6	ENSP00000252288.1
GAMT	ENST00000902474.1		c.637A>G	p.Thr213Ala	missense	Exon 3 of 6	ENSP00000572533.1
GAMT	ENST00000447102.8	TSL:2	c.367A>G	p.Thr123Ala	missense	Exon 3 of 5	ENSP00000403536.2

Frequencies

GnomAD3 genomes

AF:

0.0000132

AC:

AN:

151854

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD2 exomes

AF:

0.0000362

AC:

AN:

248736

AF XY:

0.0000593

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000290

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000713

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000486

AC:

AN:

1460822

Hom.:

Cov.:

AF XY:

0.0000592

AC XY:

AN XY:

726610

show subpopulations

African (AFR)

AF:

0.00

AC:

AN:

33474

American (AMR)

AF:

0.00

AC:

AN:

44668

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26112

East Asian (EAS)

AF:

0.00

AC:

AN:

39698

South Asian (SAS)

AF:

0.00

AC:

AN:

86108

European-Finnish (FIN)

AF:

0.00

AC:

AN:

52862

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5764

European-Non Finnish (NFE)

AF:

0.0000621

AC:

AN:

1111774

Other (OTH)

AF:

0.0000331

AC:

AN:

60362

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.458

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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:

0.0000132

AC:

AN:

151854

Hom.:

Cov.:

AF XY:

0.0000270

AC XY:

AN XY:

74166

show subpopulations

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

41300

American (AMR)

AF:

0.00

AC:

AN:

15270

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

3466

East Asian (EAS)

AF:

0.00

AC:

AN:

5176

South Asian (SAS)

AF:

0.00

AC:

AN:

4794

European-Finnish (FIN)

AF:

0.00

AC:

AN:

10584

Middle Eastern (MID)

AF:

0.00

AC:

AN:

316

European-Non Finnish (NFE)

AF:

0.0000294

AC:

AN:

67962

Other (OTH)

AF:

0.00

AC:

AN:

2076

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.350

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Genome Het

Variant carriers

<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:

0.0000313

Hom.:

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.000119

ClinVar

ClinVar submissions as Germline

Significance:Uncertain significance

Revision:criteria provided, multiple submitters, no conflicts

View on ClinVar

Pathogenic

VUS

Benign

Condition

Cerebral creatine deficiency syndrome (1)

Deficiency of guanidinoacetate methyltransferase (1)

Inborn genetic diseases (1)

not provided (1)

not specified (1)

Computational scores

Source: dbNSFP v4.9

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.061

BayesDel_addAF

Benign

-0.056

BayesDel_noAF

Benign

-0.14

CADD

Benign

(source)

DANN

Uncertain

0.97

DEOGEN2

Uncertain

0.43

Eigen

Benign

-0.29

Eigen_PC

Benign

-0.17

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Benign

0.69

M_CAP

Uncertain

0.17

MetaRNN

Benign

0.29

MetaSVM

Benign

-0.37

MutationAssessor

Benign

1.8

PhyloP100

4.9

PrimateAI

Benign

0.44

PROVEAN

Benign

-1.7

REVEL

Uncertain

0.41

Sift

Benign

0.52

Sift4G

Benign

0.20

Polyphen

0.12

Vest4

0.42

MutPred

0.22

Loss of phosphorylation at T123 (P = 0.1097)

MVP

0.85

MPC

0.14

ClinPred

0.086

GERP RS

3.8

PromoterAI

0.045

Neutral

(source)

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.63

gMVP

0.60

Mutation Taster

=35/65

disease causing

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.020

Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Variant Effect in Transcripts

RefSeq Transcripts

Ensembl Transcripts

Frequencies

Age Distribution

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over