rs1555903332

chr20-63679947-G-A

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Very_Strong

The NM_001283009.2(RTEL1):c.1135+1G>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000687 in 1,455,008 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/2 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: RTEL1 NM_001283009.2 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 8.81

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:):

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.024852678 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.8, offset of 24, new splice context is: ttgGTgcgg. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 20-63679947-G-A is Pathogenic according to our data. Variant chr20-63679947-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 436599.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RTEL1	NM_001283009.2	c.1135+1G>A		splice_donor_variant		ENST00000360203.11
RTEL1-TNFRSF6B	NR_037882.1	n.1962+1G>A		splice_donor_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RTEL1	ENST00000360203.11	c.1135+1G>A		splice_donor_variant		5	NM_001283009.2	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1455008 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 723864

Gnomad4 AFR exome AF: 0.00

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: 9.03e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Pulmonary fibrosis Pathogenic:1

Pathogenic, no assertion criteria provided

research

Garcia Pulmonary Genetics Research Laboratory, Columbia University Irving Medical Center

Jun 09, 2022

Leukocyte telomere length (by qPCR) less than 10th percentile age-adjusted -

Dyskeratosis congenita, autosomal recessive 5;C4225346:Pulmonary fibrosis and/or bone marrow failure, Telomere-related, 3 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Invitae

May 09, 2023

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 436599). This variant has not been reported in the literature in individuals affected with RTEL1-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 13 of the RTEL1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in RTEL1 are known to be pathogenic (PMID: 23453664, 23959892, 25607374). -

Dyskeratosis congenita Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Genetic Services Laboratory, University of Chicago

Dec 12, 2017

DNA sequence analysis of the RTEL1 gene demonstrated a sequence change in the canonical splice donor site of intron 13, c.1207+1G>A (NM_032957.4). This sequence change does not appear to have been previously described in patients with RTEL1-related diseases and has also not been described as a known benign sequence change in the RTEL1 gene. This pathogenic sequence change is predicted to affect normal splicing of the RTEL1 gene and result in an abnormal protein. -

Acute myeloid leukemia Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Godley laboratory, The University of Chicago

May 16, 2020

This heterozygous variant was found in germline in a patient with early greying and co-occurring AML and gastric DLBCL diagnosed at age 48. The telomere length in lymphocytes was below the 1st percentile. The following ACMG/AMP criteria were used: PVS1 (canonical splice site variant undergoing NMD), PS4_supporting, PM2. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.33
Cadd	Pathogenic	34
Dann	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.91
FATHMM_MKL	Uncertain	0.94	D
MutationTaster	Benign	1.0	D;D;D;D
GERP RS		5.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.98		Position offset: -1

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

Publications

LitVar

Other links and lift over

dbSNP: rs1555903332; hg19: chr20-62311300;