6-33440721-C-T

Variant summary

Our verdict is Benign. The variant received -14 ACMG points: 0P and 14B. BP4_ModerateBP6_Very_StrongBS2

The NM_006772.3(SYNGAP1):​c.1677-8C>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000344 in 1,568,116 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Likely benign (★★).

Frequency

Genomes: 𝑓 0.000033 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000035 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 splice_region, intron

Scores

2
Splicing: ADA: 0.0008426
2

Clinical Significance

Benign/Likely benign criteria provided, multiple submitters, no conflicts B:3

Conservation

PhyloP100: 0.211

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: Benign. The variant received -14 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.39).
BP6
Variant 6-33440721-C-T is Benign according to our data. Variant chr6-33440721-C-T is described in ClinVar as Benign/Likely_benign. ClinVar VariationId is 448635.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
BS2
High AC in GnomAd4 at 5 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SYNGAP1NM_006772.3 linkc.1677-8C>T splice_region_variant, intron_variant Intron 10 of 18 ENST00000646630.1 NP_006763.2 Q96PV0-1A0A1U9X8L0

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SYNGAP1ENST00000646630.1 linkc.1677-8C>T splice_region_variant, intron_variant Intron 10 of 18 NM_006772.3 ENSP00000496007.1 Q96PV0-1
SYNGAP1ENST00000644458.1 linkc.1677-8C>T splice_region_variant, intron_variant Intron 10 of 18 ENSP00000495541.1 A0A2R8Y6T2
SYNGAP1ENST00000449372.7 linkc.1677-8C>T splice_region_variant, intron_variant Intron 10 of 17 5 ENSP00000416519.4 B7ZCA0
SYNGAP1ENST00000418600.7 linkc.1677-8C>T splice_region_variant, intron_variant Intron 10 of 18 5 ENSP00000403636.3 Q96PV0-2
SYNGAP1ENST00000645250.1 linkc.1500-8C>T splice_region_variant, intron_variant Intron 8 of 16 ENSP00000494861.1 A0A2R8YDS2

Frequencies

GnomAD3 genomes
AF:
0.0000329
AC:
5
AN:
152138
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:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000219
AC:
4
AN:
182462
AF XY:
0.0000206
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:
0.0000526
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000346
AC:
49
AN:
1415978
Hom.:
0
Cov.:
33
AF XY:
0.0000328
AC XY:
23
AN XY:
700646
show subpopulations
African (AFR)
AF:
0.0000623
AC:
2
AN:
32116
American (AMR)
AF:
0.00
AC:
0
AN:
37496
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25384
East Asian (EAS)
AF:
0.00
AC:
0
AN:
36826
South Asian (SAS)
AF:
0.00
AC:
0
AN:
81408
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
50614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5724
European-Non Finnish (NFE)
AF:
0.0000423
AC:
46
AN:
1087698
Other (OTH)
AF:
0.0000170
AC:
1
AN:
58712
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.477
Heterozygous variant carriers
0
3
6
9
12
15
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:
0.0000329
AC:
5
AN:
152138
Hom.:
0
Cov.:
31
AF XY:
0.0000269
AC XY:
2
AN XY:
74316
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41432
American (AMR)
AF:
0.00
AC:
0
AN:
15266
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10616
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68008
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.0000603
Hom.:
0
Bravo
AF:
0.0000264

ClinVar

Significance: Benign/Likely benign
Submissions summary: Benign:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Intellectual disability, autosomal dominant 5 Benign:1
Aug 13, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

SYNGAP1-related disorder Benign:1
Apr 29, 2020
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

not provided Benign:1
Aug 03, 2023
Athena Diagnostics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.39
CADD
Benign
11
DANN
Benign
0.94
PhyloP100
0.21
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
2.2
Mutation Taster
=100/0
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00084
dbscSNV1_RF
Benign
0.090
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: rs755438249; hg19: chr6-33408498; API