5-1294418-G-T

Variant names:

• chr5-1294418-G-T
• rs755843023
• NM_198253.3:c.468C>A

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_198253.3(TERT):​c.468C>A​(p.Cys156*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000695 in 1,437,992 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. C156C) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: TERT NM_198253.3 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.393
• Publications: 0 publications found

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

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
TERT	NM_198253.3	c.468C>A	p.Cys156*	stop_gained	Exon 2 of 16	ENST00000310581.10	NP_937983.2
TERT	NM_001193376.3	c.468C>A	p.Cys156*	stop_gained	Exon 2 of 15		NP_001180305.1
TERT	NR_149162.3	n.547C>A		non_coding_transcript_exon_variant	Exon 2 of 13
TERT	NR_149163.3	n.547C>A		non_coding_transcript_exon_variant	Exon 2 of 13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TERT	ENST00000310581.10	c.468C>A	p.Cys156*	stop_gained	Exon 2 of 16	1	NM_198253.3	ENSP00000309572.5
TERT	ENST00000334602.10	c.468C>A	p.Cys156*	stop_gained	Exon 2 of 15	1		ENSP00000334346.6
TERT	ENST00000460137.6	n.468C>A		non_coding_transcript_exon_variant	Exon 2 of 13	1		ENSP00000425003.1
TERT	ENST00000656021.1	n.468C>A		non_coding_transcript_exon_variant	Exon 2 of 17			ENSP00000499759.1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.95e-7 AC: 1 AN: 1437992 Hom.: 0 Cov.: 35 AF XY: 0.00 AC XY: 0 AN XY: 715164

African (AFR) AF: 0.00 AC: 0 AN: 33292

American (AMR) AF: 0.00 AC: 0 AN: 43832

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25904

East Asian (EAS) AF: 0.00 AC: 0 AN: 39292

South Asian (SAS) AF: 0.00 AC: 0 AN: 85088

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 36968

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5576

European-Non Finnish (NFE) AF: 9.02e-7 AC: 1 AN: 1108228

Other (OTH) AF: 0.00 AC: 0 AN: 59812

GnomAD4 genome Cov.: 34

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.62
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Benign	0.16
Eigen_PC	Benign	-0.13
FATHMM_MKL	Benign	0.073	N
PhyloP100		0.39
Vest4		0.80
GERP RS		-1.3
Mutation Taster		=3/197	disease causing (fs/PTC)

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

Other links and lift over

dbSNP: rs755843023; hg19: chr5-1294533;