rs748333558

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BS2

The NM_006772.3(SYNGAP1):​c.1285C>T​(p.Arg429Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000403 in 1,614,096 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R429Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000042 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 missense

Scores

2
10
7

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 1.74

Publications

1 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)
MIR5004 (HGNC:43532): (microRNA 5004) microRNAs (miRNAs) are short (20-24 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. miRNAs are transcribed by RNA polymerase II as part of capped and polyadenylated primary transcripts (pri-miRNAs) that can be either protein-coding or non-coding. The primary transcript is cleaved by the Drosha ribonuclease III enzyme to produce an approximately 70-nt stem-loop precursor miRNA (pre-miRNA), which is further cleaved by the cytoplasmic Dicer ribonuclease to generate the mature miRNA and antisense miRNA star (miRNA*) products. The mature miRNA is incorporated into a RNA-induced silencing complex (RISC), which recognizes target mRNAs through imperfect base pairing with the miRNA and most commonly results in translational inhibition or destabilization of the target mRNA. The RefSeq represents the predicted microRNA stem-loop. [provided by RefSeq, Sep 2009]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -4 ACMG points.

BS2
High AC in GnomAdExome4 at 62 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SYNGAP1NM_006772.3 linkc.1285C>T p.Arg429Trp missense_variant Exon 8 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.1285C>T p.Arg429Trp missense_variant Exon 8 of 19 NM_006772.3 ENSP00000496007.1 Q96PV0-1
SYNGAP1ENST00000644458.1 linkc.1285C>T p.Arg429Trp missense_variant Exon 8 of 19 ENSP00000495541.1 A0A2R8Y6T2
SYNGAP1ENST00000449372.7 linkc.1285C>T p.Arg429Trp missense_variant Exon 8 of 18 5 ENSP00000416519.4 B7ZCA0
SYNGAP1ENST00000418600.7 linkc.1285C>T p.Arg429Trp missense_variant Exon 8 of 19 5 ENSP00000403636.3 Q96PV0-2
SYNGAP1ENST00000645250.1 linkc.1108C>T p.Arg370Trp missense_variant Exon 6 of 17 ENSP00000494861.1 A0A2R8YDS2

Frequencies

GnomAD3 genomes
AF:
0.0000197
AC:
3
AN:
152206
Hom.:
0
Cov.:
32
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:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000281
AC:
7
AN:
249188
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000359
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000424
AC:
62
AN:
1461890
Hom.:
0
Cov.:
35
AF XY:
0.0000358
AC XY:
26
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000486
AC:
54
AN:
1112010
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.478
Heterozygous variant carriers
0
4
7
11
14
18
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<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:
0.0000197
AC:
3
AN:
152206
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74350
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5202
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10622
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68032
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
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:
0.0000847
Hom.:
0
Bravo
AF:
0.0000227
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Aug 01, 2016
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Oct 24, 2023
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Has not been previously published as pathogenic or benign to our knowledge -

Intellectual disability, autosomal dominant 5 Uncertain:1Benign:1
Feb 26, 2021
New York Genome Center
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The de novo heterozygous missense c.1285C>T (p.Arg429Trp) variant identified in the SYNGAP1 gene of this individual has not been reported in affected individuals in the literature. It has been reported in the ClinVar database as a variant of uncertain significance (2) and likely benign (1) [Variation ID:374457]. The variant has 0.00001971 allele frequency in the gnomAD(v3) database (3 out of 152,206 heterozygous alleles, no homozygotes) suggesting it is not a common benign allele in the populations represented in that database. The affected residue is not well conserved. In silico tools provide conflicting predictions about potential pathogenicity of this variant [CADD score = 25.9, REVEL score =0.282]. Functional studies to evaluate the functional consequences of this variant have not been reported. Given the lack of compelling evidence about its pathogenicity, the de novo heterozygous missense c.1285C>T (p.Arg429Trp) variant identified in the SYNGAP1 gene is reported here as a variant of uncertain significance. -

Jun 23, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Global developmental delay Uncertain:1
Feb 21, 2017
Claritas Genomics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.50
BayesDel_addAF
Benign
0.0037
T
BayesDel_noAF
Uncertain
-0.060
CADD
Pathogenic
34
DANN
Pathogenic
1.0
DEOGEN2
Uncertain
0.65
D;D;.;.;.;.;.;.
Eigen
Uncertain
0.46
Eigen_PC
Uncertain
0.42
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Pathogenic
0.98
.;D;D;D;D;D;D;D
M_CAP
Benign
0.011
T
MetaRNN
Uncertain
0.64
D;D;D;D;D;D;D;D
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
1.5
L;L;.;.;L;L;.;.
PhyloP100
1.7
PrimateAI
Uncertain
0.75
T
PROVEAN
Uncertain
-3.1
.;.;.;D;.;D;D;.
REVEL
Benign
0.28
Sift
Benign
0.031
.;.;.;D;.;D;D;.
Sift4G
Uncertain
0.013
.;D;.;D;D;D;D;.
Polyphen
1.0
D;D;.;D;D;D;.;.
Vest4
0.52, 0.51, 0.54, 0.50
MutPred
0.65
Loss of solvent accessibility (P = 0.1077);Loss of solvent accessibility (P = 0.1077);Loss of solvent accessibility (P = 0.1077);Loss of solvent accessibility (P = 0.1077);Loss of solvent accessibility (P = 0.1077);Loss of solvent accessibility (P = 0.1077);.;.;
MVP
0.61
MPC
2.3
ClinPred
0.71
D
GERP RS
4.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7
Varity_R
0.47
gMVP
0.86
Mutation Taster
=57/43
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.11
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: rs748333558; hg19: chr6-33405967; COSMIC: COSV99537778; COSMIC: COSV99537778; API