17-78139224-G-T

Variant summary

Our verdict is Uncertain significance. The variant received 1 ACMG points: 1P and 0B. PP3

The NM_152468.5(TMC8):​c.1886G>T​(p.Arg629Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0001 in 1,613,476 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. R629Q) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00011 ( 0 hom. )

Consequence

TMC8
NM_152468.5 missense

Scores

4
9
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 1.47

Publications

3 publications found
Variant links:
Genes affected
TMC8 (HGNC:20474): (transmembrane channel like 8) 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 8 predicted transmembrane domains and 3 leucine zipper motifs. [provided by RefSeq, Jul 2008]
TMC8 Gene-Disease associations (from GenCC):
  • epidermodysplasia verruciformis, susceptibility to, 2
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
  • epidermodysplasia verruciformis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 1 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.809

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TMC8NM_152468.5 linkc.1886G>T p.Arg629Leu missense_variant Exon 15 of 16 ENST00000318430.10 NP_689681.2 Q8IU68-1A0A024R8N8B3KXZ8

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TMC8ENST00000318430.10 linkc.1886G>T p.Arg629Leu missense_variant Exon 15 of 16 1 NM_152468.5 ENSP00000325561.4 Q8IU68-1

Frequencies

GnomAD3 genomes
AF:
0.0000394
AC:
6
AN:
152208
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000439
AC:
11
AN:
250338
AF XY:
0.0000295
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000973
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000107
AC:
156
AN:
1461268
Hom.:
0
Cov.:
33
AF XY:
0.000110
AC XY:
80
AN XY:
726912
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52822
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.000133
AC:
148
AN:
1111998
Other (OTH)
AF:
0.000116
AC:
7
AN:
60388
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
10
21
31
42
52
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000394
AC:
6
AN:
152208
Hom.:
0
Cov.:
33
AF XY:
0.0000538
AC XY:
4
AN XY:
74354
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41454
American (AMR)
AF:
0.00
AC:
0
AN:
15282
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5196
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10610
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68038
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
2
2
3
4
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000919
Hom.:
0
Bravo
AF:
0.0000453
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000116
AC:
1
ExAC
AF:
0.0000165
AC:
2
EpiCase
AF:
0.0000545
EpiControl
AF:
0.0000593

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Jun 10, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.1886G>T (p.R629L) alteration is located in exon 15 (coding exon 14) of the TMC8 gene. This alteration results from a G to T substitution at nucleotide position 1886, causing the arginine (R) at amino acid position 629 to be replaced by a leucine (L). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Epidermodysplasia verruciformis Uncertain:1
Aug 27, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine with leucine at codon 629 of the TMC8 protein (p.Arg629Leu). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and leucine. This variant is present in population databases (rs369861947, ExAC 0.003%). This variant has not been reported in the literature in individuals affected with TMC8-related conditions. 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. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.54
BayesDel_addAF
Benign
-0.078
T
BayesDel_noAF
Benign
-0.14
CADD
Uncertain
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.17
T;.
Eigen
Uncertain
0.48
Eigen_PC
Uncertain
0.42
FATHMM_MKL
Uncertain
0.77
D
LIST_S2
Benign
0.84
T;T
M_CAP
Pathogenic
0.29
D
MetaRNN
Pathogenic
0.81
D;D
MetaSVM
Uncertain
0.18
D
MutationAssessor
Pathogenic
3.0
M;.
PhyloP100
1.5
PrimateAI
Benign
0.43
T
PROVEAN
Pathogenic
-4.8
D;.
REVEL
Uncertain
0.58
Sift
Uncertain
0.0020
D;.
Sift4G
Uncertain
0.0090
D;D
Polyphen
0.99
D;.
Vest4
0.57
MVP
0.82
MPC
0.53
ClinPred
0.85
D
GERP RS
4.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.0
Varity_R
0.57
gMVP
0.75
Mutation Taster
=88/12
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs369861947; hg19: chr17-76135305; API