chr5-1253750-T-C

Variant names:

• chr5-1253750-T-C
• NM_198253.3:c.3377A>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_198253.3(TERT):​c.3377A>G​(p.Asp1126Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. D1126D) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: TERT NM_198253.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.12
• 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

ENSG00000287486 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• 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.3377A>G	p.Asp1126Gly	missense_variant	Exon 16 of 16	ENST00000310581.10	NP_937983.2
TERT	NM_001193376.3	c.3188A>G	p.Asp1063Gly	missense_variant	Exon 15 of 15		NP_001180305.1
TERT	NR_149162.3	n.3085A>G		non_coding_transcript_exon_variant	Exon 13 of 13
TERT	NR_149163.3	n.3049A>G		non_coding_transcript_exon_variant	Exon 13 of 13

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
TERT	ENST00000310581.10	c.3377A>G	p.Asp1126Gly	missense_variant	Exon 16 of 16	1	NM_198253.3	ENSP00000309572.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Dyskeratosis congenita Uncertain:1

Nov 14, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.D1126G variant (also known as c.3377A>G), located in coding exon 16 of the TERT gene, results from an A to G substitution at nucleotide position 3377. The aspartic acid at codon 1126 is replaced by glycine, an amino acid with similar properties. This amino acid position is conserved. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.070
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.90	D;.
Eigen	Uncertain	0.28
Eigen_PC	Benign	0.15
FATHMM_MKL	Uncertain	0.76	D
LIST_S2	Uncertain	0.87	D;D
M_CAP	Pathogenic	0.82	D
MetaRNN	Uncertain	0.72	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.8	M;.
PhyloP100		1.1
PrimateAI	Uncertain	0.52	T
PROVEAN	Uncertain	-4.2	D;D
REVEL	Pathogenic	0.71
Sift	Uncertain	0.0040	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;D
Vest4		0.31
MutPred		0.49		Loss of stability (P = 0.0076);.;
MVP		0.97
MPC		2.5
ClinPred		0.98	D
GERP RS		3.8
Varity_R		0.58
gMVP		0.79
Mutation Taster		=58/42	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

Other links and lift over

hg19: chr5-1253865;