rs780314191

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_006772.3(SYNGAP1):​c.509+5A>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,614,054 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 2/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

SYNGAP1
NM_006772.3 splice_region, intron

Scores

2
Splicing: ADA: 0.0001559
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:1

Conservation

PhyloP100: -1.10

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: 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: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.79).
BP6
Variant 6-33432811-A-C is Benign according to our data. Variant chr6-33432811-A-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 392790.
BS1
Variant frequency is greater than expected in population sas. GnomAdExome4 allele frequency = 0.0000137 (20/1461878) while in subpopulation SAS AF = 0.00022 (19/86256). AF 95% confidence interval is 0.000143. There are 0 homozygotes in GnomAdExome4. There are 15 alleles in the male GnomAdExome4 subpopulation. Median coverage is 38. This position passed quality control check.
BS2
High AC in GnomAdExome4 at 20 AD,Unknown gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SYNGAP1NM_006772.3 linkc.509+5A>C splice_region_variant, intron_variant Intron 5 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.509+5A>C splice_region_variant, intron_variant Intron 5 of 18 NM_006772.3 ENSP00000496007.1 Q96PV0-1
SYNGAP1ENST00000644458.1 linkc.509+5A>C splice_region_variant, intron_variant Intron 5 of 18 ENSP00000495541.1 A0A2R8Y6T2
SYNGAP1ENST00000449372.7 linkc.509+5A>C splice_region_variant, intron_variant Intron 5 of 17 5 ENSP00000416519.4 B7ZCA0
SYNGAP1ENST00000418600.7 linkc.509+5A>C splice_region_variant, intron_variant Intron 5 of 18 5 ENSP00000403636.3 Q96PV0-2
SYNGAP1ENST00000645250.1 linkc.332+5A>C splice_region_variant, intron_variant Intron 3 of 16 ENSP00000494861.1 A0A2R8YDS2

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152176
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:
0.000207
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000199
AC:
5
AN:
251446
AF XY:
0.0000368
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:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000137
AC:
20
AN:
1461878
Hom.:
0
Cov.:
38
AF XY:
0.0000206
AC XY:
15
AN XY:
727242
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.000220
AC:
19
AN:
86256
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53414
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112008
Other (OTH)
AF:
0.0000166
AC:
1
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.452
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:
152176
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74344
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41448
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
68034
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Intellectual disability, autosomal dominant 5 Uncertain:1Benign:1
Oct 02, 2019
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 04, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not provided Uncertain:1
Jan 13, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.509+5A>C variant in the SYNGAP1 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. This variant is predicted to damage the natural splice donor site in intron 5, which may cause abnormal gene splicing. However, in the absence of RNA/functional studies, the actual effect of this sequence change in this individual is unknown. The c.509+5A>C variant was not observed in approximately 6500 individuals of European and African American ancestry in the NHLBI Exome Sequencing Project, indicating it is not a common benign variant in these populations. We interpret c.509+5A>C as a variant of uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.79
CADD
Benign
7.7
DANN
Benign
0.79
PhyloP100
-1.1
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00016
dbscSNV1_RF
Benign
0.040
SpliceAI score (max)
0.33
Details are displayed if max score is > 0.2
DS_DG_spliceai
0.33
Position offset: 29

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs780314191; hg19: chr6-33400588; API