rs878855262

Positions:

• chr14-95103391-G-GT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_177438.3(DICER1):​c.4004_4005insA​(p.Tyr1335Ter) variant causes a stop gained, frameshift change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. Y1335Y) has been classified as Likely benign. Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 33)
• Consequence: DICER1 NM_177438.3 stop_gained, frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 7.99

Genes affected

DICER1 (HGNC:17098): (dicer 1, ribonuclease III) This gene encodes a protein possessing an RNA helicase motif containing a DEXH box in its amino terminus and an RNA motif in the carboxy terminus. The encoded protein functions as a ribonuclease and is required by the RNA interference and small temporal RNA (stRNA) pathways to produce the active small RNA component that represses gene expression. This protein also acts as a strong antiviral agent with activity against RNA viruses, including the Zika and SARS-CoV-2 viruses. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2021]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 14-95103391-G-GT is Pathogenic according to our data. Variant chr14-95103391-G-GT is described in ClinVar as [Pathogenic]. Clinvar id is 242098.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DICER1	NM_177438.3	c.4004_4005insA	p.Tyr1335Ter	stop_gained, frameshift_variant	21/27	ENST00000343455.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DICER1	ENST00000343455.8	c.4004_4005insA	p.Tyr1335Ter	stop_gained, frameshift_variant	21/27	1	NM_177438.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Center for Genomic Medicine, Rigshospitalet, Copenhagen University Hospital	Aug 15, 2023	- -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jun 16, 2023	Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is a known mechanism of disease; Not observed at significant frequency in large population cohorts (gnomAD); Has not been previously published as a germline pathogenic or benign variant to our knowledge; This variant is associated with the following publications: (PMID: 24481001, 26628006, 19556464) -

DICER1-related tumor predisposition Pathogenic:2

Pathogenic, criteria provided, single submitter	curation	Foulkes Cancer Genetics LDI, Lady Davis Institute for Medical Research	Jul 01, 2019	ACMG criteria met: PVS1, PM2, PP4 -
Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Apr 23, 2022	This variant is not present in population databases (gnomAD no frequency). This sequence change creates a premature translational stop signal (p.Tyr1335*) in the DICER1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in DICER1 are known to be pathogenic (PMID: 19556464, 21266384). This variant has not been reported in the literature in individuals affected with DICER1-related conditions. ClinVar contains an entry for this variant (Variation ID: 242098). For these reasons, this variant has been classified as Pathogenic. -

Hereditary cancer-predisposing syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

May 11, 2023

The c.4004dupA pathogenic mutation, located in coding exon 20 of the DICER1 gene, results from a duplication of A at nucleotide position 4004, causing a translational frameshift with a predicted alternate stop codon (p.Y1335*). In one study, this alteration was identified in a female patient diagnosed with rhabdomyosarcoma (Akhavanfard S et al. Nat Commun, 2020 May;11:2206). This alteration is expected to result in loss of function by premature protein truncation or nonsense-mediated mRNA decay. As such, this alteration is interpreted as a disease-causing mutation. -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs878855262; hg19: chr14-95569728;