14-95124596-C-T

Variant names:

• chr14-95124596-C-T
• rs1555374798
• NM_177438.3:c.976G>A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 1P and 5B. PP2 BP4 BS2

The NM_177438.3(DICER1):​c.976G>A​(p.Val326Ile) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000479 in 1,461,468 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000048 (0 hom.)
• Consequence: DICER1 NM_177438.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.35

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 Likely_benign. Variant got -4 ACMG points.

• PP2: Missense variant in the DICER1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 43 curated pathogenic missense variants (we use a threshold of 10). The gene has 111 curated benign missense variants. Gene score misZ: 4.2261 (above the threshold of 3.09). Trascript score misZ: 6.1353 (above the threshold of 3.09). GenCC associations: The gene is linked to goiter, multinodular 1, with or without Sertoli-Leydig cell tumors, global developmental delay - lung cysts - overgrowth - Wilms tumor syndrome, DICER1-related tumor predisposition, DICER1 syndrome, pleuropulmonary blastoma.
• BP4: Computational evidence support a benign effect (MetaRNN=0.3817622).
• BS2: High AC in GnomAdExome4 at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DICER1	NM_177438.3	c.976G>A	p.Val326Ile	missense_variant	Exon 8 of 27	ENST00000343455.8	NP_803187.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DICER1	ENST00000343455.8	c.976G>A	p.Val326Ile	missense_variant	Exon 8 of 27	1	NM_177438.3	ENSP00000343745.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000479 AC: 7 AN: 1461468 Hom.: 0 Cov.: 33 AF XY: 0.00000688 AC XY: 5 AN XY: 726988

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Global developmental delay - lung cysts - overgrowth - Wilms tumor syndrome Uncertain:1

Oct 05, 2023

Baylor Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

DICER1-related tumor predisposition Uncertain:1

Aug 04, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with isoleucine, which is neutral and non-polar, at codon 326 of the DICER1 protein (p.Val326Ile). This variant is not present in population databases (gnomAD no frequency). 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: 543630). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt DICER1 protein function with a negative predictive value of 80%. 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. -

Hereditary cancer-predisposing syndrome Uncertain:1

Aug 17, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.V326I variant (also known as c.976G>A), located in coding exon 7 of the DICER1 gene, results from a G to A substitution at nucleotide position 976. The valine at codon 326 is replaced by isoleucine, an amino acid with highly similar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. 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
AlphaMissense	Benign	0.22
BayesDel_addAF	Benign	-0.057	T
BayesDel_noAF	Benign	-0.32
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Benign	0.19	T;T;T;T;.
Eigen	Uncertain	0.51
Eigen_PC	Uncertain	0.58
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.95	.;.;D;.;D
M_CAP	Benign	0.022	T
MetaRNN	Benign	0.38	T;T;T;T;T
MetaSVM	Benign	-0.94	T
MutationAssessor	Benign	1.0	L;L;L;L;L
PrimateAI	Uncertain	0.65	T
PROVEAN	Benign	0.26	N;N;N;N;N
REVEL	Benign	0.11
Sift	Benign	0.13	T;T;T;T;T
Sift4G	Benign	0.65	T;T;T;T;T
Polyphen		0.97	D;D;D;D;.
Vest4		0.46
MutPred		0.31		Gain of sheet (P = 0.0073);Gain of sheet (P = 0.0073);Gain of sheet (P = 0.0073);Gain of sheet (P = 0.0073);Gain of sheet (P = 0.0073);
MVP		0.62
MPC		0.92
ClinPred		0.77	D
GERP RS		5.5
Varity_R		0.17
gMVP		0.20

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: rs1555374798; hg19: chr14-95590933;