chr14-95096448-C-A

Variant names:

• chr14-95096448-C-A
• rs878855267
• NM_177438.3:c.4472G>T

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 2P and 6B. PM2 BP4_Moderate BS2

The NM_177438.3(DICER1):​c.4472G>T​(p.Ser1491Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,880 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 16/22 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. S1491N) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: DICER1 NM_177438.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 0.853
• 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: Likely_benign. The variant received -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.13003248).
• BS2: High AC in GnomAdExome4 at 5 AD,Unknown gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DICER1	NM_177438.3	c.4472G>T	p.Ser1491Ile	missense_variant	Exon 23 of 27	ENST00000343455.8	NP_803187.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DICER1	ENST00000343455.8	c.4472G>T	p.Ser1491Ile	missense_variant	Exon 23 of 27	1	NM_177438.3	ENSP00000343745.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461880 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727238

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000450 AC: 5 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60394

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

Nov 24, 2015

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, this is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature. This sequence change replaces serine with isoleucine at codon 1491 of the DICER1 protein (p.Ser1491Ile). The serine residue is weakly conserved and there is a large physicochemical difference between serine and isoleucine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Oct 10, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.S1491I variant (also known as c.4472G>T), located in coding exon 22 of the DICER1 gene, results from a G to T substitution at nucleotide position 4472. The serine at codon 1491 is replaced by isoleucine, an amino acid with 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	0.088
BayesDel_addAF	Benign	-0.021	T
BayesDel_noAF	Benign	-0.27
CADD	Benign	15
DANN	Uncertain	0.98
DEOGEN2	Benign	0.24	T;T;T;T;.;.
Eigen	Benign	-0.37
Eigen_PC	Benign	-0.42
FATHMM_MKL	Benign	0.37	N
LIST_S2	Uncertain	0.88	.;.;D;.;D;D
M_CAP	Benign	0.037	D
MetaRNN	Benign	0.13	T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.69	N;N;N;N;.;N
PhyloP100		0.85
PrimateAI	Benign	0.35	T
PROVEAN	Benign	-0.13	N;N;N;N;N;N
REVEL	Benign	0.058
Sift	Uncertain	0.022	D;D;D;D;D;D
Sift4G	Benign	0.22	T;T;T;T;T;T
Polyphen		0.14	B;B;B;B;.;.
Vest4		0.25
MutPred		0.40		Loss of phosphorylation at S1491 (P = 0.0223);Loss of phosphorylation at S1491 (P = 0.0223);Loss of phosphorylation at S1491 (P = 0.0223);Loss of phosphorylation at S1491 (P = 0.0223);.;Loss of phosphorylation at S1491 (P = 0.0223);
MVP		0.76
MPC		1.1
ClinPred		0.37	T
GERP RS		2.1
Varity_R		0.061
gMVP		0.31
Mutation Taster		=84/16	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs878855267; hg19: chr14-95562785;