rs147521473

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_198253.3(TERT):​c.1936C>T​(p.Arg646Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000514 in 1,614,074 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R646H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000059 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000051 ( 0 hom. )

Consequence

TERT
NM_198253.3 missense

Scores

1
3
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:7B:1

Conservation

PhyloP100: -0.108

Publications

2 publications found
Variant links:
Genes affected
TERT (HGNC:11730): (telomerase reverse transcriptase) Telomerase is a ribonucleoprotein polymerase that maintains telomere ends by addition of the telomere repeat TTAGGG. The enzyme consists of a protein component with reverse transcriptase activity, encoded by this gene, and an RNA component which serves as a template for the telomere repeat. Telomerase expression plays a role in cellular senescence, as it is normally repressed in postnatal somatic cells resulting in progressive shortening of telomeres. Deregulation of telomerase expression in somatic cells may be involved in oncogenesis. Studies in mouse suggest that telomerase also participates in chromosomal repair, since de novo synthesis of telomere repeats may occur at double-stranded breaks. Alternatively spliced variants encoding different isoforms of telomerase reverse transcriptase have been identified; the full-length sequence of some variants has not been determined. Alternative splicing at this locus is thought to be one mechanism of regulation of telomerase activity. [provided by RefSeq, Jul 2008]
TERT Gene-Disease associations (from GenCC):
  • pulmonary fibrosis and/or bone marrow failure, Telomere-related, 1
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics
  • dyskeratosis congenita, autosomal dominant 2
    Inheritance: AR, AD, SD, Unknown Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen, Laboratory for Molecular Medicine
  • acute myeloid leukemia
    Inheritance: AD Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • dyskeratosis congenita
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Hoyeraal-Hreidarsson syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • melanoma, cutaneous malignant, susceptibility to, 9
    Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.091836214).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
TERTNM_198253.3 linkc.1936C>T p.Arg646Cys missense_variant Exon 4 of 16 ENST00000310581.10 NP_937983.2 O14746-1
TERTNM_001193376.3 linkc.1936C>T p.Arg646Cys missense_variant Exon 4 of 15 NP_001180305.1 O14746-3
TERTNR_149162.3 linkn.2015C>T non_coding_transcript_exon_variant Exon 4 of 13
TERTNR_149163.3 linkn.2015C>T non_coding_transcript_exon_variant Exon 4 of 13

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
TERTENST00000310581.10 linkc.1936C>T p.Arg646Cys missense_variant Exon 4 of 16 1 NM_198253.3 ENSP00000309572.5 O14746-1

Frequencies

GnomAD3 genomes
AF:
0.0000591
AC:
9
AN:
152214
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.0000482
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000882
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000398
AC:
10
AN:
251332
AF XY:
0.0000515
show subpopulations
Gnomad AFR exome
AF:
0.0000615
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:
0.0000792
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000506
AC:
74
AN:
1461742
Hom.:
0
Cov.:
32
AF XY:
0.0000481
AC XY:
35
AN XY:
727162
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:
26134
East Asian (EAS)
AF:
0.000101
AC:
4
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.0000188
AC:
1
AN:
53288
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000585
AC:
65
AN:
1112000
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
4
9
13
18
22
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000591
AC:
9
AN:
152332
Hom.:
0
Cov.:
34
AF XY:
0.0000537
AC XY:
4
AN XY:
74478
show subpopulations
African (AFR)
AF:
0.0000481
AC:
2
AN:
41584
American (AMR)
AF:
0.0000654
AC:
1
AN:
15302
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5180
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68030
Other (OTH)
AF:
0.00
AC:
0
AN:
2116
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.525
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:
0.000116
Hom.:
0
Bravo
AF:
0.0000680
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000233
AC:
2
ExAC
AF:
0.0000412
AC:
5
EpiCase
AF:
0.00
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:7Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Dyskeratosis congenita, autosomal dominant 2 Uncertain:2
Oct 18, 2023
Baylor Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 23, 2024
St. Jude Molecular Pathology, St. Jude Children's Research Hospital
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The TERT c.1936C>T (p.Arg646Cys) missense change has a maximum subpopulation frequency of 0.0077% in gnomAD v2.1.1 (https://gnomad.broadinstitute.org/). The in silico tool REVEL predicts a benign effect on protein function, but to our knowledge this prediction has not been confirmed by functional studies. This variant occurs in a gene where missense variants are more likely to be damaging based on methods described by Lek et al. (PMID: 27535533). This variant has been reported in an individual with Hodgkin lymphoma (PMID: 35106810). To our knowledge, this variant has not been reported in individuals with clinical features of dyskeratosis congenita. In summary, the evidence currently available is insufficient to determine the clinical significance of this variant. It has therefore been classified as of uncertain significance. -

Dyskeratosis congenita Uncertain:2
Jan 11, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R646C variant (also known as c.1936C>T), located in coding exon 4 of the TERT gene, results from a C to T substitution at nucleotide position 1936. The arginine at codon 646 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is not well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Jul 02, 2021
Sema4, Sema4
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:curation

- -

not specified Uncertain:1
Jun 16, 2021
Genetic Services Laboratory, University of Chicago
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

DNA sequence analysis of the TERT gene demonstrated a sequence change, c.1936C>T, in exon 4 that results in an amino acid change, p.Arg646Cys. This sequence change has been described in gnomAD with a frequency of 0.0077% in the Non-Finnish European sub-population (dbSNP rs147521473). The p.Arg646Cys change affects a poorly conserved amino acid residue located in a domain of the TERT protein that is \ known to be functional. The p.Arg646Cys substitution appears to be tolerated using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL). This sequence change does not appear to have been previously described in patients with TERT-related disorders. Due to the lack of sufficient evidences, the clinical significance of the p.Arg646Cys change remains unknown at this time. -

not provided Uncertain:1
Feb 09, 2025
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In silico analysis indicates that this missense variant does not alter protein structure/function; Identified as a presumed germline variant in an individual with myeloid neoplasm and observed in an individual with cirrhosis (PMID: 30964210, 35106810); This variant is associated with the following publications: (PMID: 35106810, 30964210) -

TERT-related disorder Uncertain:1
Apr 26, 2024
PreventionGenetics, part of Exact Sciences
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

The TERT c.1936C>T variant is predicted to result in the amino acid substitution p.Arg646Cys. This variant has been reported in an individual with cirrhosis and in an individual with therapy-related myeloid neoplasm (Chiu et al. 2019. PubMed ID: 30964210; Gurnari et al. 2022. PubMed ID: 35106810). This variant is reported in 0.0077% of alleles in individuals of European (non-Finnish) descent in gnomAD. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Idiopathic Pulmonary Fibrosis;C3151443:Dyskeratosis congenita, autosomal dominant 2 Benign:1
Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.099
BayesDel_addAF
Benign
-0.14
T
BayesDel_noAF
Benign
-0.25
CADD
Benign
14
DANN
Benign
0.96
DEOGEN2
Uncertain
0.50
D;.
Eigen
Benign
-0.93
Eigen_PC
Benign
-0.99
FATHMM_MKL
Benign
0.015
N
LIST_S2
Benign
0.75
T;T
M_CAP
Pathogenic
0.30
D
MetaRNN
Benign
0.092
T;T
MetaSVM
Uncertain
-0.13
T
MutationAssessor
Benign
1.6
L;L
PhyloP100
-0.11
PrimateAI
Benign
0.24
T
PROVEAN
Benign
-1.6
N;N
REVEL
Benign
0.25
Sift
Benign
0.056
T;T
Sift4G
Uncertain
0.054
T;T
Polyphen
0.054
B;B
Vest4
0.14
MVP
0.28
MPC
1.4
ClinPred
0.044
T
GERP RS
-2.0
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Varity_R
0.077
gMVP
0.62
Mutation Taster
=65/35
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
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: rs147521473; hg19: chr5-1280287; COSMIC: COSV57215955; API