chr6-33420300-C-G

Position:

chr6-33420300-C-G

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2PP2BP4_Moderate

The NM_006772.3(SYNGAP1):c.36C>G(p.Ser12Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000259 in 1,541,614 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. S12S) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 28)

Exomes 𝑓: 0.0000022 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.666

Variant links:

Genes affected

SYNGAP1 (HGNC:11497): (synaptic Ras GTPase activating protein 1) This gene encodes a Ras GTPase activating protein that is a member of the N-methyl-D-aspartate receptor complex. The N-terminal domain of the protein contains a Ras-GAP domain, a pleckstrin homology domain, and a C2 domain that may be involved in binding of calcium and phospholipids. The C-terminal domain consists of a ten histidine repeat region, serine and tyrosine phosphorylation sites, and a T/SXV motif required for postsynaptic scaffold protein interaction. The encoded protein negatively regulates Ras, Rap and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor trafficking to the postsynaptic membrane to regulate synaptic plasticity and neuronal homeostasis. Allelic variants of this gene are associated with intellectual disability and autism spectrum disorder. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2016]

SYNGAP1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SYNGAP1. . Gene score misZ 5.6047 (greater than the threshold 3.09). Trascript score misZ 7.6762 (greater than threshold 3.09). GenCC has associacion of gene with autosomal dominant non-syndromic intellectual disability, complex neurodevelopmental disorder, intellectual disability, autosomal dominant 5, SYNGAP1-related developmental and epileptic encephalopathy, myoclonic-astatic epilepsy.

BP4

Computational evidence support a benign effect (MetaRNN=0.12877625).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SYNGAP1	NM_006772.3 linkuse as main transcript	c.36C>G	p.Ser12Arg	missense_variant	1/19	ENST00000646630.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SYNGAP1	ENST00000646630.1 linkuse as main transcript	c.36C>G	p.Ser12Arg	missense_variant	1/19		NM_006772.3	P1	Q96PV0-1

Frequencies

GnomAD3 genomes

AF:

0.00000659

AC:

AN:

151808

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:

0.00000216

AC:

AN:

1389806

Hom.:

Cov.:

AF XY:

0.00000292

AC XY:

AN XY:

685266

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:

0.00000279

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000659

AC:

AN:

151808

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74156

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

Bravo

AF:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Intellectual disability, autosomal dominant 5

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 14, 2023

This sequence change replaces serine, which is neutral and polar, with arginine, which is basic and polar, at codon 12 of the SYNGAP1 protein (p.Ser12Arg). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with SYNGAP1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1962619). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SYNGAP1 protein function with a negative predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.50

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.47

CADD

Uncertain

DANN

Uncertain

0.98

DEOGEN2

Benign

0.048

T;T;.;.;.;.

Eigen

Benign

-0.52

Eigen_PC

Benign

-0.41

FATHMM_MKL

Uncertain

0.80

LIST_S2

Benign

0.64

.;T;T;T;T;T

M_CAP

Benign

0.055

MetaRNN

Benign

0.13

T;T;T;T;T;T

MetaSVM

Benign

-0.94

MutationAssessor

Benign

0.0

N;N;.;.;N;N

MutationTaster

Benign

0.99

N;N;N

PrimateAI

Pathogenic

0.91

PROVEAN

Benign

-0.30

.;.;.;N;.;N

REVEL

Benign

0.097

Sift

Pathogenic

0.0

.;.;.;D;.;D

Sift4G

Benign

0.063

.;T;.;T;T;T

Polyphen

0.0

B;B;.;.;.;.

Vest4

0.21, 0.21, 0.14

MutPred

0.31

Gain of methylation at S12 (P = 0.0065);Gain of methylation at S12 (P = 0.0065);Gain of methylation at S12 (P = 0.0065);Gain of methylation at S12 (P = 0.0065);Gain of methylation at S12 (P = 0.0065);Gain of methylation at S12 (P = 0.0065);

MVP

0.043

MPC

1.2

ClinPred

0.17

GERP RS

2.8

Varity_R

0.13

gMVP

0.32

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.

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