rs1554122236

Variant names:

• chr6-33443276-G-C
• rs1554122236
• NM_006772.3:c.2724G>C

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 2P and 3B. PM2 BP4_Moderate BP6

The NM_006772.3(SYNGAP1):​c.2724G>C​(p.Gln908His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,350 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SYNGAP1 NM_006772.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3 B:1
• Conservation: PhyloP100: 2.88
• Publications: 0 publications found

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

Our verdict: Likely_benign. The variant received -1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.25687528).
• BP6: Variant 6-33443276-G-C is Benign according to our data. Variant chr6-33443276-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 436926.

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.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SYNGAP1	NM_006772.3	MANE Select	c.2724G>C	p.Gln908His	missense	Exon 15 of 19	NP_006763.2	A0A1U9X8L0
	SYNGAP1	NM_001130066.2		c.2682G>C	p.Gln894His	missense	Exon 14 of 18	NP_001123538.1	B7ZCA0
	SYNGAP1-AS1	NR_174954.1		n.329+3330C>G		intron	N/A

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SYNGAP1	ENST00000646630.1	MANE Select	c.2724G>C	p.Gln908His	missense	Exon 15 of 19	ENSP00000496007.1	Q96PV0-1
	SYNGAP1	ENST00000644458.1		c.2724G>C	p.Gln908His	missense	Exon 15 of 19	ENSP00000495541.1	A0A2R8Y6T2
	SYNGAP1	ENST00000449372.7	TSL:5	c.2682G>C	p.Gln894His	missense	Exon 14 of 18	ENSP00000416519.4	B7ZCA0

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249270 AF XY: 0.00

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: 0.00000884

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460350 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 726600

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: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51900

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60386

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	1	-	Inborn genetic diseases (1)
-	-	1	Intellectual disability, autosomal dominant 5 (1)
-	1	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.31
BayesDel_addAF	Benign	-0.12	T
BayesDel_noAF	Benign	-0.42
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.043	T
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.52
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.89	D
M_CAP	Benign	0.025	T
MetaRNN	Benign	0.26	T
MetaSVM	Benign	-1.2	T
MutationAssessor	Benign	1.6	L
PhyloP100		2.9
PrimateAI	Pathogenic	0.82	D
PROVEAN	Benign	-0.70	N
REVEL	Benign	0.11
Sift	Uncertain	0.013	D
Sift4G	Uncertain	0.053	T
Polyphen		1.0	D
Vest4		0.24
MutPred		0.19		Gain of methylation at R905 (P = 0.0446)
MVP		0.22
MPC		1.1
ClinPred		0.58	D
GERP RS		4.5
Varity_R		0.16
gMVP		0.54
Mutation Taster		=49/51	disease causing

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

Other links and lift over

dbSNP: rs1554122236; hg19: chr6-33411053;