rs1197755223

Positions:

• chr14-95103743-G-A
• chr14-95103743-G-C
• chr14-95103743-G-T

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.3653C>T​(p.Ser1218Phe) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. S1218C) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: DICER1 NM_177438.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.05

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=0.20752767).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DICER1	NM_177438.3	c.3653C>T	p.Ser1218Phe	missense_variant	21/27	ENST00000343455.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DICER1	ENST00000343455.8	c.3653C>T	p.Ser1218Phe	missense_variant	21/27	1	NM_177438.3	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

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

Invitae

Aug 07, 2019

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but 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. This variant is not present in population databases (ExAC no frequency). This sequence change replaces serine with phenylalanine at codon 1218 of the DICER1 protein (p.Ser1218Phe). The serine residue is weakly conserved and there is a large physicochemical difference between serine and phenylalanine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 16, 2023

The p.S1218F variant (also known as c.3653C>T), located in coding exon 20 of the DICER1 gene, results from a C to T substitution at nucleotide position 3653. The serine at codon 1218 is replaced by phenylalanine, an amino acid with highly dissimilar properties. This amino acid position is conserved. 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	0.11
BayesDel_addAF	Uncertain	0.027	T
BayesDel_noAF	Benign	-0.20
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.34	T;T;T;T;.;.
Eigen	Benign	-0.12
Eigen_PC	Benign	0.10
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Uncertain	0.89	.;.;D;.;D;D
M_CAP	Benign	0.027	D
MetaRNN	Benign	0.21	T;T;T;T;T;T
MetaSVM	Benign	-0.70	T
MutationAssessor	Benign	0.90	L;L;L;L;.;L
MutationTaster	Benign	0.96	N;N;N;N;N;N
PrimateAI	Benign	0.30	T
PROVEAN	Benign	-1.6	N;N;N;N;N;N
REVEL	Benign	0.084
Sift	Benign	0.033	D;D;D;D;D;D
Sift4G	Benign	0.21	T;T;T;T;T;T
Polyphen		0.031	B;B;B;B;.;.
Vest4		0.39
MutPred		0.49		Loss of disorder (P = 0.0043);Loss of disorder (P = 0.0043);Loss of disorder (P = 0.0043);Loss of disorder (P = 0.0043);.;Loss of disorder (P = 0.0043);
MVP		0.82
MPC		0.55
ClinPred		0.42	T
GERP RS		5.4
Varity_R		0.10
gMVP		0.42

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: rs1197755223; hg19: chr14-95570080;