rs747929833

Variant summary

Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_006772.3(SYNGAP1):​c.2353C>T​(p.Arg785Cys) variant causes a missense change. The variant allele was found at a frequency of 0.000018 in 1,612,102 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R785H) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000019 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 missense

Scores

3
6
10

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 4.49

Publications

0 publications found
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-AS1 (HGNC:53831): (SYNGAP1 antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.23202339).
BS2
High AC in GnomAdExome4 at 28 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SYNGAP1NM_006772.3 linkc.2353C>T p.Arg785Cys missense_variant Exon 15 of 19 ENST00000646630.1 NP_006763.2 Q96PV0-1A0A1U9X8L0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SYNGAP1ENST00000646630.1 linkc.2353C>T p.Arg785Cys missense_variant Exon 15 of 19 NM_006772.3 ENSP00000496007.1 Q96PV0-1
SYNGAP1ENST00000644458.1 linkc.2353C>T p.Arg785Cys missense_variant Exon 15 of 19 ENSP00000495541.1 A0A2R8Y6T2
SYNGAP1ENST00000449372.7 linkc.2311C>T p.Arg771Cys missense_variant Exon 14 of 18 5 ENSP00000416519.4 B7ZCA0
SYNGAP1ENST00000418600.7 linkc.2353C>T p.Arg785Cys missense_variant Exon 15 of 19 5 ENSP00000403636.3 Q96PV0-2
SYNGAP1ENST00000645250.1 linkc.2176C>T p.Arg726Cys missense_variant Exon 13 of 17 ENSP00000494861.1 A0A2R8YDS2

Frequencies

GnomAD3 genomes
AF:
0.00000661
AC:
1
AN:
151356
Hom.:
0
Cov.:
31
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
GnomAD2 exomes
AF:
0.0000120
AC:
3
AN:
249238
AF XY:
0.0000222
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000893
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000192
AC:
28
AN:
1460746
Hom.:
0
Cov.:
32
AF XY:
0.0000206
AC XY:
15
AN XY:
726716
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33460
American (AMR)
AF:
0.00
AC:
0
AN:
44684
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39674
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86244
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53194
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000216
AC:
24
AN:
1111234
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60362
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.457
Heterozygous variant carriers
0
2
4
6
8
10
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:
0.00000661
AC:
1
AN:
151356
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
73902
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41130
American (AMR)
AF:
0.00
AC:
0
AN:
15222
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3466
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5078
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4800
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10556
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
312
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
67808
Other (OTH)
AF:
0.00
AC:
0
AN:
2074
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome 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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000248
AC:
3

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
Oct 16, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 785 of the SYNGAP1 protein (p.Arg785Cys). This variant is present in population databases (rs747929833, gnomAD 0.006%). 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: 469149). 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. 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
Pathogenic
0.66
BayesDel_addAF
Benign
-0.063
T
BayesDel_noAF
Benign
-0.33
CADD
Pathogenic
28
DANN
Uncertain
0.99
DEOGEN2
Benign
0.31
T;T;.;.;.;.;.;.
Eigen
Benign
0.00086
Eigen_PC
Benign
0.096
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.92
.;D;D;D;D;D;D;D
M_CAP
Benign
0.020
T
MetaRNN
Benign
0.23
T;T;T;T;T;T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Uncertain
2.4
M;M;.;.;M;M;.;.
PhyloP100
4.5
PrimateAI
Uncertain
0.68
T
PROVEAN
Pathogenic
-4.9
.;.;.;D;.;D;D;.
REVEL
Benign
0.13
Sift
Uncertain
0.011
.;.;.;D;.;D;D;.
Sift4G
Uncertain
0.0020
.;D;.;D;D;D;D;.
Polyphen
0.14
B;B;.;.;B;B;.;.
Vest4
0.25, 0.30, 0.39, 0.33
MutPred
0.35
Loss of MoRF binding (P = 0.0061);Loss of MoRF binding (P = 0.0061);Loss of MoRF binding (P = 0.0061);.;Loss of MoRF binding (P = 0.0061);Loss of MoRF binding (P = 0.0061);.;.;
MVP
0.16
MPC
1.8
ClinPred
0.87
D
GERP RS
3.6
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.53
gMVP
0.67
Mutation Taster
=77/23
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.030
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: rs747929833; hg19: chr6-33410682; API