NM_177438.3:c.2026C>A

Variant names:

• chr14-95113106-G-T
• rs878855246
• NM_177438.3:c.2026C>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_177438.3(DICER1):​c.2026C>A​(p.Arg676Arg) variant causes a synonymous change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. R676R) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: DICER1 NM_177438.3 synonymous
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.65
• Publications: 0 publications found

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]

DICER1 Gene-Disease associations (from GenCC):

• DICER1-related tumor predisposition

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• pleuropulmonary blastoma

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• DICER1 syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• global developmental delay - lung cysts - overgrowth - Wilms tumor syndrome

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DICER1	NM_177438.3	c.2026C>A	p.Arg676Arg	synonymous_variant	Exon 12 of 27	ENST00000343455.8	NP_803187.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DICER1	ENST00000343455.8	c.2026C>A	p.Arg676Arg	synonymous_variant	Exon 12 of 27	1	NM_177438.3	ENSP00000343745.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary cancer-predisposing syndrome Uncertain:1

Jul 24, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2026C>A variant (also known as p.R676R), located in coding exon 11 of the DICER1 gene, results from a C to A substitution at nucleotide position 2026. This nucleotide substitution does not change the arginine at codon 676. This nucleotide position is well conserved in available vertebrate species. In silico splice site analysis for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.37
CADD	Benign	17
DANN	Benign	0.69
PhyloP100		3.6
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.26		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.26		Position offset: 45
DS_DL_spliceai		0.20		Position offset: -14

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

Other links and lift over

dbSNP: rs878855246; hg19: chr14-95579443;