6-33420300-C-G

Variant summary

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

The NM_006772.3(SYNGAP1):ā€‹c.36C>Gā€‹(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 (ā˜…). Synonymous variant affecting the same amino acid position (i.e. S12S) has been classified as Likely benign.

Frequency

Genomes: š‘“ 0.0000066 ( 0 hom., cov: 28)
Exomes š‘“: 0.0000022 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 missense

Scores

2
3
14

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]

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
SYNGAP1NM_006772.3 linkuse as main transcriptc.36C>G p.Ser12Arg missense_variant 1/19 ENST00000646630.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
SYNGAP1ENST00000646630.1 linkuse as main transcriptc.36C>G p.Ser12Arg missense_variant 1/19 NM_006772.3 P1Q96PV0-1

Frequencies

GnomAD3 genomes
AF:
0.00000659
AC:
1
AN:
151808
Hom.:
0
Cov.:
28
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:
3
AN:
1389806
Hom.:
0
Cov.:
31
AF XY:
0.00000292
AC XY:
2
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:
1
AN:
151808
Hom.:
0
Cov.:
28
AF XY:
0.00
AC XY:
0
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 submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpDec 14, 2023This 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
T
BayesDel_noAF
Benign
-0.47
CADD
Uncertain
24
DANN
Uncertain
0.98
DEOGEN2
Benign
0.048
T;T;.;.;.;.
Eigen
Benign
-0.52
Eigen_PC
Benign
-0.41
FATHMM_MKL
Uncertain
0.80
D
LIST_S2
Benign
0.64
.;T;T;T;T;T
M_CAP
Benign
0.055
D
MetaRNN
Benign
0.13
T;T;T;T;T;T
MetaSVM
Benign
-0.94
T
MutationAssessor
Benign
0.0
N;N;.;.;N;N
MutationTaster
Benign
0.99
N;N;N
PrimateAI
Pathogenic
0.91
D
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
T
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.

Other links and lift over

dbSNP: rs1362587238; hg19: chr6-33388077; API