rs863224915

Positions:

• chr20-63685798-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_001283009.2(RTEL1):​c.1274T>C​(p.Ile425Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: RTEL1 NM_001283009.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.67

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]

RTEL1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.902

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
RTEL1	NM_001283009.2	c.1274T>C	p.Ile425Thr	missense_variant	16/35	ENST00000360203.11	NP_001269938.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
RTEL1	ENST00000360203.11	c.1274T>C	p.Ile425Thr	missense_variant	16/35	5	NM_001283009.2	ENSP00000353332.5
RTEL1	ENST00000508582.7	c.1346T>C	p.Ile449Thr	missense_variant	16/35	2		ENSP00000424307.2
RTEL1	ENST00000370018.7	c.1274T>C	p.Ile425Thr	missense_variant	16/35	1		ENSP00000359035.3
RTEL1-TNFRSF6B	ENST00000492259.6	n.1358T>C		non_coding_transcript_exon_variant	14/35	5		ENSP00000457428.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Mar 09, 2023

This sequence change replaces isoleucine, which is neutral and non-polar, with threonine, which is neutral and polar, at codon 425 of the RTEL1 protein (p.Ile425Thr). 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. An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. ClinVar contains an entry for this variant (Variation ID: 242480). This missense change has been observed in individuals with dyskeratosis congenita (PMID: 25326637, 28507545). This variant is not present in population databases (gnomAD no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.0
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.65	D;.;.;.
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.22
FATHMM_MKL	Uncertain	0.90	D
LIST_S2	Uncertain	0.88	D;D;D;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.90	D;D;D;D
MetaSVM	Uncertain	0.62	D
MutationAssessor	Pathogenic	3.2	M;.;M;.
PrimateAI	Uncertain	0.60	T
PROVEAN	Pathogenic	-4.5	D;D;D;.
REVEL	Pathogenic	0.66
Sift	Uncertain	0.0010	D;D;D;.
Sift4G	Uncertain	0.0080	D;D;D;D
Polyphen		0.64	P;P;B;.
Vest4		0.70
MutPred		0.53		Loss of stability (P = 0.0047);.;Loss of stability (P = 0.0047);.;
MVP		0.82
ClinPred		0.99	D
GERP RS		4.7
Varity_R		0.53
gMVP		0.84

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

Other links and lift over

dbSNP: rs863224915; hg19: chr20-62317151;