chr3-14131678-A-G

Position:

• chr3-14131678-A-G

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_Moderate BS2

The NM_024334.3(TMEM43):​c.392+4A>G variant causes a splice donor region, intron change. The variant allele was found at a frequency of 0.00000959 in 1,459,236 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000096 (0 hom.)
• Consequence: TMEM43 NM_024334.3 splice_donor_region, intron
• Scores: Splicing: ADA: 0.8838
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 6.07

Genes affected

TMEM43 (HGNC:28472): (transmembrane protein 43) This gene belongs to the TMEM43 family. Defects in this gene are the cause of familial arrhythmogenic right ventricular dysplasia type 5 (ARVD5), also known as arrhythmogenic right ventricular cardiomyopathy type 5 (ARVC5). Arrhythmogenic right ventricular dysplasia is an inherited disorder, often involving both ventricles, and is characterized by ventricular tachycardia, heart failure, sudden cardiac death, and fibrofatty replacement of cardiomyocytes. This gene contains a response element for PPAR gamma (an adipogenic transcription factor), which may explain the fibrofatty replacement of the myocardium, a characteristic pathological finding in ARVC. [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Likely_benign. Variant got -6 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.28).
• BS2: High AC in GnomAdExome4 at 14 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
TMEM43	NM_024334.3	c.392+4A>G		splice_donor_region_variant, intron_variant		ENST00000306077.5	NP_077310.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
TMEM43	ENST00000306077.5	c.392+4A>G		splice_donor_region_variant, intron_variant		1	NM_024334.3	ENSP00000303992	P1
TMEM43	ENST00000432444.2	c.*422+4A>G		splice_donor_region_variant, intron_variant, NMD_transcript_variant		3		ENSP00000395617

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000959 AC: 14 AN: 1459236 Hom.: 0 Cov.: 29 AF XY: 0.0000110 AC XY: 8 AN XY: 726092

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: 0.0000126

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Jul 31, 2012

The 392+4A>G variant in TMEM43 has not been reported in the literature nor previ ously identified by our laboratory. It has also not been detected in 2 large and broad populations (European and African American) screened by the NHLBI Exome S equencing Project (http://evs.gs.washington.edu/EVS), which is consistent with a role in disease. This variant is located in the 5' splice region and computatio nal tools do suggest a slight impact to splicing (please note that their accurac y is unknown). Additional information is needed to fully assess the clinical sig nificance of this variant. -

Arrhythmogenic right ventricular dysplasia 5 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 19, 2022

In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 46144). This variant has not been reported in the literature in individuals affected with TMEM43-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change falls in intron 4 of the TMEM43 gene. It does not directly change the encoded amino acid sequence of the TMEM43 protein. It affects a nucleotide within the consensus splice site. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.28
CADD	Benign	11
DANN	Benign	0.95

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.88
dbscSNV1_RF	Benign	0.56
SpliceAI score (max)		0.58		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.58		Position offset: -4

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs397517382; hg19: chr3-14173178;