NM_001099404.2:c.1141-3C>T

Variant names:

• chr3-38606151-G-A
• rs41312433
• NM_001099404.2:c.1141-3C>T

Variant summary

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

The NM_001099404.2(SCN5A):​c.1141-3C>T variant causes a splice region, intron change. The variant allele was found at a frequency of 0.00000205 in 1,460,766 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 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: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SCN5A NM_001099404.2 splice_region, intron
• Scores: Splicing: ADA: 0.07778
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 3.84
• Publications: 0 publications found

Genes affected

SCN5A (HGNC:10593): (sodium voltage-gated channel alpha subunit 5) The protein encoded by this gene is an integral membrane protein and tetrodotoxin-resistant voltage-gated sodium channel subunit. This protein is found primarily in cardiac muscle and is responsible for the initial upstroke of the action potential in an electrocardiogram. Defects in this gene have been associated with long QT syndrome type 3 (LQT3), atrial fibrillation, cardiomyopathy, and Brugada syndrome 1, all autosomal dominant cardiac diseases. Alternative splicing results in several transcript variants encoding different isoforms. [provided by RefSeq, May 2022]

SCN5A Gene-Disease associations (from GenCC):

• Brugada syndrome

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• Brugada syndrome 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Laboratory for Molecular Medicine, Genomics England PanelApp, G2P, Ambry Genetics
• cardiac rhythm disease

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• dilated cardiomyopathy 1E

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• familial long QT syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• long QT syndrome 3

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• progressive familial heart block, type 1A

  Inheritance: AD, SD Classification: STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics
• sick sinus syndrome 1

  Inheritance: AR, AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
• atrial standstill

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial atrial fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial isolated dilated cardiomyopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial sick sinus syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• paroxysmal familial ventricular fibrillation

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• progressive familial heart block

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• arrhythmogenic right ventricular cardiomyopathy

  Inheritance: AD Classification: LIMITED Submitted by: ClinGen
• catecholaminergic polymorphic ventricular tachycardia

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• congenital heart disease

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen
• short QT syndrome

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

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 (BayesDel_noAF=-0.24).
• BP6: Variant 3-38606151-G-A is Benign according to our data. Variant chr3-38606151-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 2141315.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001099404.2. 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
	SCN5A	NM_001099404.2	MANE Plus Clinical	c.1141-3C>T		splice_region intron	N/A	NP_001092874.1	H9KVD2
	SCN5A	NM_000335.5	MANE Select	c.1141-3C>T		splice_region intron	N/A	NP_000326.2
	SCN5A	NM_198056.3		c.1141-3C>T		splice_region intron	N/A	NP_932173.1	Q14524-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SCN5A	ENST00000413689.6	TSL:5 MANE Plus Clinical	c.1141-3C>T		splice_region intron	N/A	ENSP00000410257.1	H9KVD2
	SCN5A	ENST00000423572.7	TSL:1 MANE Select	c.1141-3C>T		splice_region intron	N/A	ENSP00000398266.2	Q14524-2
	SCN5A	ENST00000333535.9	TSL:1	c.1141-3C>T		splice_region intron	N/A	ENSP00000328968.4	Q14524-1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460766 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 726692

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33468

American (AMR) AF: 0.00 AC: 0 AN: 44700

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86220

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53086

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5566

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1111574

Other (OTH) AF: 0.00 AC: 0 AN: 60326

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0000000000000565104), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	Cardiac arrhythmia (1)
-	1	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.24
CADD	Benign	14
DANN	Benign	0.96
PhyloP100		3.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.078
dbscSNV1_RF	Benign	0.11
SpliceAI score (max)		0.050		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: rs41312433; hg19: chr3-38647642;