2-166198763-T-G

Position:

• chr2-166198763-T-G

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM2 PP3 PP5_Moderate

The NM_001365536.1(SCN9A):​c.5876A>C​(p.Asp1959Ala) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: SCN9A NM_001365536.1 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.21

Genes affected

SCN9A (HGNC:10597): (sodium voltage-gated channel alpha subunit 9) This gene encodes a voltage-gated sodium channel which plays a significant role in nociception signaling. Mutations in this gene have been associated with primary erythermalgia, channelopathy-associated insensitivity to pain, and paroxysmal extreme pain disorder. [provided by RefSeq, Aug 2009]

SCN1A-AS1 (HGNC:54069): (SCN1A and SCN9A antisense RNA 1)

ACMG classification

Verdict is Uncertain_significance. Variant got 5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.779
• PP5: Variant 2-166198763-T-G is Pathogenic according to our data. Variant chr2-166198763-T-G is described in ClinVar as [Likely_pathogenic]. Clinvar id is 408574.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SCN9A	NM_001365536.1	c.5876A>C	p.Asp1959Ala	missense_variant	27/27	ENST00000642356.2	NP_001352465.1
SCN1A-AS1	NR_110260.1	n.432-876T>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SCN9A	ENST00000642356.2	c.5876A>C	p.Asp1959Ala	missense_variant	27/27		NM_001365536.1	ENSP00000495601	P1
SCN1A-AS1	ENST00000651574.1	n.1110-876T>G		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Generalized epilepsy with febrile seizures plus, type 7;C2752089:Neuropathy, hereditary sensory and autonomic, type 2A Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 02, 2020

Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant identified in the SCN9A gene is located in the cytoplasmic C-terminal region of the resulting protein (PMID: 25348405). It is unclear how this variant impacts the function of this protein. This variant has been shown to arise de novo in an individual affected intractable generalized epilepsy and static encephalopathy (Invitae database). This variant is not present in population databases (ExAC no frequency). This sequence change replaces aspartic acid with alanine at codon 1948 of the SCN9A protein (p.Asp1948Ala). The aspartic acid residue is highly conserved and there is a moderate physicochemical difference between aspartic acid and alanine. In summary, this variant is a rare missense change that has been observed to occur de novo in an affected individual. This evidence indicates that the variant is pathogenic, but additional data is needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.31
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.63	.;D;.;.;D;.
Eigen	Uncertain	0.46
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Uncertain	0.88	D;.;D;D;D;D
M_CAP	Uncertain	0.20	D
MetaRNN	Pathogenic	0.78	D;D;D;D;D;D
MetaSVM	Pathogenic	0.92	D
MutationAssessor	Pathogenic	3.0	.;M;.;.;M;M
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Uncertain	0.54	T
PROVEAN	Pathogenic	-6.6	D;.;.;.;.;D
REVEL	Pathogenic	0.66
Sift	Pathogenic	0.0	D;.;.;.;.;D
Sift4G	Uncertain	0.022	D;D;.;.;.;D
Vest4		0.39
MutPred		0.35		Gain of glycosylation at S1946 (P = 0.069);.;Gain of glycosylation at S1946 (P = 0.069);.;.;.;
MVP		0.87
MPC		0.62
ClinPred		1.0	D
GERP RS		5.9
Varity_R		0.82
gMVP		0.43

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: rs1060502047; hg19: chr2-167055273;