NM_198253.3:c.670C>T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_198253.3(TERT):c.670C>T(p.Arg224Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000699 in 1,431,266 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R224G) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 34)

Exomes 𝑓: 7.0e-7 ( 0 hom. )

Consequence

TERT
NM_198253.3 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 1.32

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.21059692).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TERT	NM_198253.3 link	c.670C>T	p.Arg224Cys	missense_variant	Exon 2 of 16	ENST00000310581.10	NP_937983.2	O14746-1
TERT	NM_001193376.3 link	c.670C>T	p.Arg224Cys	missense_variant	Exon 2 of 15		NP_001180305.1	O14746-3
TERT	NR_149162.3 link	n.749C>T		non_coding_transcript_exon_variant	Exon 2 of 13
TERT	NR_149163.3 link	n.749C>T		non_coding_transcript_exon_variant	Exon 2 of 13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	UniProt
TERT	ENST00000310581.10 link	c.670C>T	p.Arg224Cys	missense_variant	Exon 2 of 16	1	NM_198253.3	ENSP00000309572.5	O14746-1
TERT	ENST00000334602.10 link	c.670C>T	p.Arg224Cys	missense_variant	Exon 2 of 15	1		ENSP00000334346.6	O14746-3
TERT	ENST00000460137.6 link	n.670C>T		non_coding_transcript_exon_variant	Exon 2 of 13	1		ENSP00000425003.1	O14746-4
TERT	ENST00000656021.1 link	n.670C>T		non_coding_transcript_exon_variant	Exon 2 of 17			ENSP00000499759.1	A0A590UK92

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000521

AC:

AN:

191896

Hom.:

AF XY:

0.00

AC XY:

AN XY:

107570

show subpopulations

Gnomad AFR exome

AF:

0.0000945

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

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:

6.99e-7

AC:

AN:

1431266

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

711102

show subpopulations

Gnomad4 AFR exome

AF:

0.0000303

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:

0.00

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

Alfa

AF:

0.0000434

Hom.:

ExAC

AF:

0.00000866

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Idiopathic Pulmonary Fibrosis;C3151443:Dyskeratosis congenita, autosomal dominant 2

Uncertain:1

Oct 07, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 224 of the TERT protein (p.Arg224Cys). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with TERT-related conditions. ClinVar contains an entry for this variant (Variation ID: 581289). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt TERT protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. 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. -

Dyskeratosis congenita

Uncertain:1

Feb 15, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.R224C variant (also known as c.670C>T), located in coding exon 2 of the TERT gene, results from a C to T substitution at nucleotide position 670. The arginine at codon 224 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.17

BayesDel_addAF

Uncertain

0.14

BayesDel_noAF

Uncertain

-0.040

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.47

T;.

Eigen

Benign

-0.62

Eigen_PC

Benign

-0.74

FATHMM_MKL

Benign

0.074

LIST_S2

Uncertain

0.88

D;D

M_CAP

Pathogenic

0.88

MetaRNN

Benign

0.21

T;T

MetaSVM

Uncertain

0.32

MutationAssessor

Benign

2.0

M;M

PrimateAI

Uncertain

0.68

PROVEAN

Uncertain

-2.8

D;D

REVEL

Benign

0.24

Sift

Uncertain

0.0050

D;D

Sift4G

Uncertain

0.014

D;D

Polyphen

0.32

B;B

Vest4

0.24

MutPred

0.38

Loss of methylation at R224 (P = 0.0042);Loss of methylation at R224 (P = 0.0042);

MVP

0.52

MPC

2.5

ClinPred

0.58

GERP RS

2.6

Varity_R

0.37

gMVP

0.67

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.0

Details are displayed if max score is > 0.2

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over