rs769471844

chr17-78124181-T-Achr17-78124181-T-Cchr17-78124181-T-G

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1 PM2 PP3_Strong PP5_Moderate

The NM_001127198.5(TMC6):c.892-2A>T variant causes a splice acceptor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,611,062 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000041 (0 hom.)
• Consequence: TMC6 NM_001127198.5 splice_acceptor
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Pathogenic criteria provided, single submitter P:1 O:1
• Conservation: PhyloP100: 7.42

Genes affected

TMC6 (HGNC:18021): (transmembrane channel like 6) Epidermodysplasia verruciformis (EV) is an autosomal recessive dermatosis characterized by abnormal susceptibility to human papillomaviruses (HPVs) and a high rate of progression to squamous cell carcinoma on sun-exposed skin. EV is caused by mutations in either of two adjacent genes located on chromosome 17q25.3. Both of these genes encode integral membrane proteins that localize to the endoplasmic reticulum and are predicted to form transmembrane channels. This gene encodes a transmembrane channel-like protein with 10 transmembrane domains and 2 leucine zipper motifs. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PVS1: Splicing variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 17-78124181-T-A is Pathogenic according to our data. Variant chr17-78124181-T-A is described in ClinVar as [Pathogenic]. Clinvar id is 4751.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr17-78124181-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TMC6	NM_001127198.5	c.892-2A>T		splice_acceptor_variant		ENST00000590602.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TMC6	ENST00000590602.6	c.892-2A>T		splice_acceptor_variant		2	NM_001127198.5	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152124 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000192

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000404 AC: 1 AN: 247538 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 134322

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000411 AC: 6 AN: 1458938 Hom.: 0 Cov.: 34 AF XY: 0.00000276 AC XY: 2 AN XY: 725786

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000151

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152124 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74302

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.000192

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1 Other:1

Revision: criteria provided, single submitter

Submissions by phenotype

Epidermodysplasia verruciformis Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Dec 22, 2023

This sequence change affects an acceptor splice site in intron 8 of the TMC6 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in TMC6 are known to be pathogenic (PMID: 15042430, 17139267). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with epidermodysplasia verruciformis (PMID: 15042430, 36268689). It has also been observed to segregate with disease in related individuals. ClinVar contains an entry for this variant (Variation ID: 4751). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Epidermodysplasia verruciformis, susceptibility to, 1 Other:1

risk factor, no assertion criteria provided

literature only

OMIM

Jan 01, 2004

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.58	D
BayesDel_noAF	Benign	-0.30
Cadd	Pathogenic	30
Dann	Benign	0.85
Eigen	Uncertain	0.64
Eigen_PC	Uncertain	0.35
FATHMM_MKL	Uncertain	0.95	D
MutationTaster	Benign	1.0	D;D;D;D;D;D
GERP RS		1.7
RBP_binding_hub_radar		1.1
RBP_regulation_power_radar		2.2

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.75
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.52		Position offset: -43
DS_AL_spliceai		0.99		Position offset: -2

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

Publications

LitVar

Other links and lift over

dbSNP: rs769471844; hg19: chr17-76120262;