rs1555366685

Variant names:

• chr14-95093917-T-C
• rs1555366685
• NM_177438.3:c.5335A>G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM1 PM2

The NM_177438.3(DICER1):​c.5335A>G​(p.Lys1779Glu) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. 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. K1779R) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 33)
• Consequence: DICER1 NM_177438.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.61
• 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 4 ACMG points.

• PM1: In a domain RNase III 2 (size 158) in uniprot entity DICER_HUMAN there are 35 pathogenic changes around while only 4 benign (90%) in NM_177438.3
• 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.5335A>G	p.Lys1779Glu	missense_variant	Exon 24 of 27	ENST00000343455.8	NP_803187.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DICER1	ENST00000343455.8	c.5335A>G	p.Lys1779Glu	missense_variant	Exon 24 of 27	1	NM_177438.3	ENSP00000343745.3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

DICER1-related tumor predisposition Uncertain:1

Jun 15, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, this variant 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: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a DICER1-related disease. This sequence change replaces lysine with glutamic acid at codon 1779 of the DICER1 protein (p.Lys1779Glu). The lysine residue is highly conserved and there is a small physicochemical difference between lysine and glutamic acid. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Benign	0.24	T;T;T;T;.;.
Eigen	Benign	0.19
Eigen_PC	Uncertain	0.31
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.92	.;.;D;.;D;D
M_CAP	Uncertain	0.15	D
MetaRNN	Uncertain	0.48	T;T;T;T;T;T
MetaSVM	Benign	-0.38	T
MutationAssessor	Benign	1.4	L;L;L;L;.;L
PhyloP100		7.6
PrimateAI	Pathogenic	0.88	D
PROVEAN	Benign	0.080	N;N;N;N;N;N
REVEL	Uncertain	0.50
Sift	Benign	0.47	T;T;T;T;T;D
Sift4G	Benign	0.33	T;T;T;T;T;T
Polyphen		0.99	D;D;D;D;.;.
Vest4		0.66
MutPred		0.47		Loss of ubiquitination at K1779 (P = 0.0043);Loss of ubiquitination at K1779 (P = 0.0043);Loss of ubiquitination at K1779 (P = 0.0043);Loss of ubiquitination at K1779 (P = 0.0043);.;Loss of ubiquitination at K1779 (P = 0.0043);
MVP		0.89
MPC		2.0
ClinPred		0.70	D
GERP RS		5.3
Varity_R		0.49
gMVP		0.63
Mutation Taster		=28/72	disease causing

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

Other links and lift over

dbSNP: rs1555366685; hg19: chr14-95560254;