14-95096143-C-A

Position:

• chr14-95096143-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2 PP2 BP4_Moderate

The NM_177438.3(DICER1):​c.4777G>T​(p.Val1593Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,888 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DICER1 NM_177438.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 2.65

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 Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), DICER1. . Gene score misZ 4.2261 (greater than the threshold 3.09). Trascript score misZ 6.1353 (greater than threshold 3.09). GenCC has associacion of gene with 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=0.11169845).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DICER1	NM_177438.3	c.4777G>T	p.Val1593Leu	missense_variant	23/27	ENST00000343455.8	NP_803187.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DICER1	ENST00000343455.8	c.4777G>T	p.Val1593Leu	missense_variant	23/27	1	NM_177438.3	ENSP00000343745	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727248

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

DICER1-related tumor predisposition Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 24, 2021

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The leucine amino acid residue is found in multiple mammalian species, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with DICER1-related conditions. ClinVar contains an entry for this variant (Variation ID: 825166). This variant is not present in population databases (ExAC no frequency). This sequence change replaces valine with leucine at codon 1593 of the DICER1 protein (p.Val1593Leu). The valine residue is moderately conserved and there is a small physicochemical difference between valine and leucine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 30, 2018

The p.V1593L variant (also known as c.4777G>T), located in coding exon 22 of the DICER1 gene, results from a G to T substitution at nucleotide position 4777. The valine at codon 1593 is replaced by leucine, an amino acid with highly similar properties. This amino acid position is well 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	0.14
BayesDel_addAF	Benign	-0.047	T
BayesDel_noAF	Benign	-0.30
CADD	Benign	14
DANN	Benign	0.94
DEOGEN2	Benign	0.23	T;T;T;T;.;.
Eigen	Benign	-0.50
Eigen_PC	Benign	-0.43
FATHMM_MKL	Uncertain	0.84	D
LIST_S2	Benign	0.75	.;.;T;.;T;T
M_CAP	Benign	0.021	T
MetaRNN	Benign	0.11	T;T;T;T;T;T
MetaSVM	Benign	-0.65	T
MutationAssessor	Benign	1.0	L;L;L;L;.;L
MutationTaster	Benign	1.0	N;N;N;N;N;N
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-0.13	N;N;N;N;N;N
REVEL	Benign	0.096
Sift	Benign	0.53	T;T;T;T;T;T
Sift4G	Benign	0.66	T;T;T;T;T;T
Polyphen		0.0	B;B;B;B;.;.
Vest4		0.14
MutPred		0.32		Gain of loop (P = 0.069);Gain of loop (P = 0.069);Gain of loop (P = 0.069);Gain of loop (P = 0.069);.;Gain of loop (P = 0.069);
MVP		0.68
MPC		0.48
ClinPred		0.32	T
GERP RS		4.3
Varity_R		0.15
gMVP		0.33

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: rs1060503644; hg19: chr14-95562480;