rs1553479077

chr2-166228707-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_001365536.1(SCN9A):c.4190T>C(p.Leu1397Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 13/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L1397I) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SCN9A NM_001365536.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.29

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 Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.985

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SCN9A	NM_001365536.1	c.4190T>C	p.Leu1397Pro	missense_variant	22/27	ENST00000642356.2
SCN1A-AS1	NR_110260.1	n.612-19488A>G		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SCN9A	ENST00000642356.2	c.4190T>C	p.Leu1397Pro	missense_variant	22/27		NM_001365536.1	P1
SCN1A-AS1	ENST00000651574.1	n.1290-19488A>G		intron_variant, non_coding_transcript_variant

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain: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 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Jun 07, 2019

This sequence change replaces leucine with proline at codon 1386 of the SCN9A protein (p.Leu1386Pro). The leucine residue is highly conserved and there is a moderate physicochemical difference between leucine and proline. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a SCN9A-related disease. This variant identified in the SCN9A gene is located in the transmembrane spanning DIII-S5/S6 region of the resulting protein (PMID: 25348405). It is unclear how this variant impacts the function of this protein. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies. In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.59
Cadd	Pathogenic	27
Dann	Pathogenic	1.0
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.87	D;.;D;D;D;D
M_CAP	Pathogenic	0.60	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationTaster	Benign	1.0	D;D;D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-6.7	D;.;.;.;.;D
REVEL	Pathogenic	1.0
Sift	Pathogenic	0.0	D;.;.;.;.;D
Sift4G	Pathogenic	0.0	D;D;.;.;.;D
Vest4		0.98
MutPred		0.91		Loss of stability (P = 0.1115);.;Loss of stability (P = 0.1115);.;.;.;
MVP		0.90
MPC		0.71
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.97
gMVP		0.99

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: rs1553479077; hg19: chr2-167085217;