rs878855249

chr14-95111324-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_177438.3(DICER1):c.2249C>G(p.Pro750Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,126 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P750T) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: DICER1 NM_177438.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 8.11

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 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant where missense usually causes diseases, DICER1
• BP4: Computational evidence support a benign effect (MetaRNN=0.3622157).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DICER1	NM_177438.3	c.2249C>G	p.Pro750Arg	missense_variant	14/27	ENST00000343455.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DICER1	ENST00000343455.8	c.2249C>G	p.Pro750Arg	missense_variant	14/27	1	NM_177438.3	P1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152126 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 32

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152126 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74308

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000655

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

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

Feb 09, 2016

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 in individuals with a DICER1-related disease. This sequence change replaces proline with arginine at codon 750 of the DICER1 protein (p.Pro750Arg). The proline residue is moderately conserved and there is a moderate physicochemical difference between proline and arginine. -

Hereditary cancer-predisposing syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 08, 2021

The p.P750R variant (also known as c.2249C>G), located in coding exon 13 of the DICER1 gene, results from a C to G substitution at nucleotide position 2249. The proline at codon 750 is replaced by arginine, an amino acid with dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. 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	Uncertain	0.45
BayesDel_addAF	Uncertain	0.10	D
BayesDel_noAF	Benign	-0.090
Cadd	Uncertain	24
Dann	Uncertain	1.0
DEOGEN2	Benign	0.41	T;T;T;T;.
Eigen	Benign	0.16
Eigen_PC	Uncertain	0.36
FATHMM_MKL	Pathogenic	0.99	D
M_CAP	Benign	0.021	T
MetaRNN	Benign	0.36	T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N;N;N;N;N
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.88	D
PROVEAN	Benign	-1.3	N;N;N;N;N
REVEL	Benign	0.20
Sift	Benign	0.13	T;T;T;T;T
Sift4G	Benign	0.22	T;T;T;T;T
Polyphen		0.30	B;B;B;B;.
Vest4		0.70
MutPred		0.32		Gain of MoRF binding (P = 0.002);Gain of MoRF binding (P = 0.002);Gain of MoRF binding (P = 0.002);Gain of MoRF binding (P = 0.002);Gain of MoRF binding (P = 0.002);
MVP		0.70
MPC		0.94
ClinPred		0.72	D
GERP RS		5.7
Varity_R		0.16
gMVP		0.64

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs878855249; hg19: chr14-95577661;