20-63659410-AG-A

Variant names:

• chr20-63659410-AG-A
• NM_001283009.2:c.9delG

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PVS1_Strong PM2 PP5_Moderate

The NM_001283009.2(RTEL1):​c.9delG​(p.Ile4fs) variant causes a frameshift 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 Pathogenic (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: RTEL1 NM_001283009.2 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 1.80

Genes affected

RTEL1 (HGNC:15888): (regulator of telomere elongation helicase 1) This gene encodes a DNA helicase which functions in the stability, protection and elongation of telomeres and interacts with proteins in the shelterin complex known to protect telomeres during DNA replication. Mutations in this gene have been associated with dyskeratosis congenita and Hoyerall-Hreidarsson syndrome. Read-through transcription of this gene into the neighboring downstream gene, which encodes tumor necrosis factor receptor superfamily, member 6b, generates a non-coding transcript. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Sep 2013]

RTEL1-TNFRSF6B (HGNC:44095): (RTEL1-TNFRSF6B readthrough (NMD candidate)) This locus represents naturally occurring read-through transcription between the neighboring RTEL1 (regulator of telomere elongation helicase 1) and TNFRSF6B (tumor necrosis factor receptor superfamily, member 6b, decoy) genes on chromosome 20. The read-through transcript is a candidate for nonsense-mediated mRNA decay (NMD), and is unlikely to produce a protein product. [provided by RefSeq, Feb 2011]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 10 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 20-63659410-AG-A is Pathogenic according to our data. Variant chr20-63659410-AG-A is described in ClinVar as [Pathogenic]. Clinvar id is 1048767.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
RTEL1	NM_001283009.2	c.9delG	p.Ile4fs	frameshift_variant	Exon 2 of 35	ENST00000360203.11	NP_001269938.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
RTEL1	ENST00000360203.11	c.9delG	p.Ile4fs	frameshift_variant	Exon 2 of 35	5	NM_001283009.2	ENSP00000353332.5
RTEL1	ENST00000508582.7	c.9delG	p.Ile4fs	frameshift_variant	Exon 2 of 35	2		ENSP00000424307.2
RTEL1	ENST00000370018.7	c.9delG	p.Ile4fs	frameshift_variant	Exon 2 of 35	1		ENSP00000359035.3
RTEL1-TNFRSF6B	ENST00000492259.6	n.9delG		non_coding_transcript_exon_variant	Exon 1 of 35	5		ENSP00000457428.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Pulmonary fibrosis and/or bone marrow failure, Telomere-related, 3 Pathogenic:1

Mar 29, 2021

Johns Hopkins Genomics, Johns Hopkins University

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

RTEL1 c.9delG is absent from a large population dataset and has not been reported in ClinVar nor the literature, to our knowledge. This frameshift variant is predicted to lead to a premature stop codon in exon 2 (the first coding exon) of RTEL1, likely leading to nonsense-mediated decay and lack of protein production. We consider RTEL1 c.9delG to be pathogenic. -

Computational scores

Source: dbNSFP v4.3

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr20-62290763;