chr20-63692957-C-A

Position:

• chr20-63692957-C-A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_001283009.2(RTEL1):​c.2805C>A​(p.Leu935=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,228 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign 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. L935L) has been classified as Likely benign.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: RTEL1 NM_001283009.2 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.561

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_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.65).
• BP7: Synonymous conserved (PhyloP=-0.561 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
RTEL1	NM_001283009.2	c.2805C>A	p.Leu935=	synonymous_variant	29/35	ENST00000360203.11
RTEL1-TNFRSF6B	NR_037882.1	n.3632C>A		non_coding_transcript_exon_variant	29/38

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
RTEL1	ENST00000360203.11	c.2805C>A	p.Leu935=	synonymous_variant	29/35	5	NM_001283009.2	A2

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152228 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000207

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 33

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152228 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74366

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.65
CADD	Benign	0.19
DANN	Benign	0.87
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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

LitVar

Other links and lift over

dbSNP: rs12625047; hg19: chr20-62324310;