chr6-33423572-C-A

Variant summary

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

The NM_006772.3(SYNGAP1):​c.163C>A​(p.Gln55Lys) variant causes a missense change. The variant allele was found at a frequency of 0.0000149 in 1,614,044 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 (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 missense

Scores

1
7
10

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 4.53

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 Gene-Disease associations (from GenCC):
  • complex neurodevelopmental disorder
    Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
  • intellectual disability, autosomal dominant 5
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, G2P, Labcorp Genetics (formerly Invitae)
  • autosomal dominant non-syndromic intellectual disability
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • SYNGAP1-related developmental and epileptic encephalopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myoclonic-astatic epilepsy
    Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

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=0.24966493).
BS2
High AC in GnomAdExome4 at 23 AD,Unknown gene.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_006772.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SYNGAP1
NM_006772.3
MANE Select
c.163C>Ap.Gln55Lys
missense
Exon 2 of 19NP_006763.2A0A1U9X8L0
SYNGAP1
NM_001130066.2
c.163C>Ap.Gln55Lys
missense
Exon 2 of 18NP_001123538.1B7ZCA0

Ensembl Transcripts

Sel.
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
SYNGAP1
ENST00000646630.1
MANE Select
c.163C>Ap.Gln55Lys
missense
Exon 2 of 19ENSP00000496007.1Q96PV0-1
SYNGAP1
ENST00000644458.1
c.163C>Ap.Gln55Lys
missense
Exon 2 of 19ENSP00000495541.1A0A2R8Y6T2
SYNGAP1
ENST00000449372.7
TSL:5
c.163C>Ap.Gln55Lys
missense
Exon 2 of 18ENSP00000416519.4B7ZCA0

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152180
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.0000157
AC:
23
AN:
1461864
Hom.:
0
Cov.:
31
AF XY:
0.0000151
AC XY:
11
AN XY:
727230
show subpopulations
African (AFR)
AF:
0.00
AC:
0
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:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5746
European-Non Finnish (NFE)
AF:
0.0000198
AC:
22
AN:
1112008
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.445
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.00000657
AC:
1
AN:
152180
Hom.:
0
Cov.:
32
AF XY:
0.0000134
AC XY:
1
AN XY:
74362
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:
0
AN:
41418
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68036
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
⚠️ 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: 0.375
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:
0.0000113
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.000259
AC:
1

ClinVar

ClinVar submissions
Significance:Uncertain significance
Revision:criteria provided, multiple submitters, no conflicts
View on ClinVar
Pathogenic
VUS
Benign
Condition
-
1
-
Inborn genetic diseases (1)
-
1
-
Intellectual disability, autosomal dominant 5 (1)

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.61
BayesDel_addAF
Benign
-0.11
T
BayesDel_noAF
Benign
-0.40
CADD
Uncertain
24
DANN
Uncertain
0.99
DEOGEN2
Benign
0.082
T
Eigen
Benign
0.17
Eigen_PC
Uncertain
0.23
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Uncertain
0.91
D
M_CAP
Benign
0.012
T
MetaRNN
Benign
0.25
T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
2.0
M
PhyloP100
4.5
PrimateAI
Uncertain
0.79
T
PROVEAN
Benign
-1.2
N
REVEL
Benign
0.085
Sift
Uncertain
0.022
D
Sift4G
Uncertain
0.032
D
Polyphen
0.14
B
Vest4
0.53
MutPred
0.48
Gain of methylation at Q55 (P = 0.0189)
MVP
0.19
MPC
1.6
ClinPred
0.80
D
GERP RS
3.7
Varity_R
0.19
gMVP
0.94
Mutation Taster
=85/15
polymorphism

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

Other links and lift over

dbSNP: rs752176449; hg19: chr6-33391349; API