rs756823385

Positions:

• chr6-33440914-G-A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PP2 PP3 BP6_Moderate BS2

The NM_006772.3(SYNGAP1):​c.1862G>A​(p.Arg621Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,461,894 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.000013 (0 hom.)
• Consequence: SYNGAP1 NM_006772.3 missense
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 10.0

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)

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SYNGAP1. . Gene score misZ 5.6047 (greater than the threshold 3.09). Trascript score misZ 7.6762 (greater than threshold 3.09). GenCC has associacion of gene with autosomal dominant non-syndromic intellectual disability, complex neurodevelopmental disorder, intellectual disability, autosomal dominant 5, SYNGAP1-related developmental and epileptic encephalopathy, myoclonic-astatic epilepsy.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.795
• BP6: Variant 6-33440914-G-A is Benign according to our data. Variant chr6-33440914-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 578137.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS2: High AC in GnomAdExome4 at 19 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SYNGAP1	NM_006772.3	c.1862G>A	p.Arg621Gln	missense_variant	11/19	ENST00000646630.1	NP_006763.2
SYNGAP1-AS1	NR_174954.1	n.330-3433C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SYNGAP1	ENST00000646630.1	c.1862G>A	p.Arg621Gln	missense_variant	11/19		NM_006772.3	ENSP00000496007	P1
SYNGAP1-AS1	ENST00000630418.1	n.378-3433C>T		intron_variant, non_coding_transcript_variant		5

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.0000159 AC: 4 AN: 251480 Hom.: 0 AF XY: 0.0000147 AC XY: 2 AN XY: 135914

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000352

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000130 AC: 19 AN: 1461894 Hom.: 0 Cov.: 39 AF XY: 0.0000151 AC XY: 11 AN XY: 727248

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000162

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

Alfa AF: 0.0000403 Hom.: 0

Bravo AF: 0.0000151

ExAC AF: 0.0000165 AC: 2

EpiCase AF: 0.0000545

EpiControl AF: 0.0000593

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual disability, autosomal dominant 5 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Dec 03, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Pathogenic	0.21
CADD	Pathogenic	33
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.91	D;D;.;.;.;.;.;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.94
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	1.0	.;D;D;D;D;D;D;D
M_CAP	Benign	0.033	D
MetaRNN	Pathogenic	0.80	D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.56	T
MutationAssessor	Pathogenic	3.9	H;H;.;.;H;H;.;.
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.79	T
PROVEAN	Uncertain	-3.9	.;.;.;D;.;D;D;.
REVEL	Uncertain	0.62
Sift	Pathogenic	0.0	.;.;.;D;.;D;D;.
Sift4G	Pathogenic	0.0	.;D;.;D;D;D;D;.
Polyphen		1.0	D;D;.;.;D;D;.;.
Vest4		0.95, 0.96, 0.93
MVP		0.78
MPC		2.5
ClinPred		1.0	D
GERP RS		5.0
Varity_R		0.83
gMVP		0.92

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

LitVar

Other links and lift over

dbSNP: rs756823385; hg19: chr6-33408691;