Genetic Variant DDX20:p.Lys91Met (chr1-111756196-A-T) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_007204.5(DDX20):c.272A>T(p.Lys91Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000269 in 1,486,652 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000022 ( 0 hom. )

Consequence

DDX20
NM_007204.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.02

Variant links:

Genes affected

DDX20 (HGNC:2743): (DEAD-box helicase 20) DEAD box proteins, characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box protein, which has an ATPase activity and is a component of the survival of motor neurons (SMN) complex. This protein interacts directly with SMN, the spinal muscular atrophy gene product, and may play a catalytic role in the function of the SMN complex on RNPs. [provided by RefSeq, Jul 2008]

DDX20 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DDX20	NM_007204.5 link	c.272A>T	p.Lys91Met	missense_variant	Exon 1 of 11	ENST00000369702.5	NP_009135.4	Q9UHI6-1Q9H4N4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DDX20	ENST00000369702.5 link	c.272A>T	p.Lys91Met	missense_variant	Exon 1 of 11	1	NM_007204.5	ENSP00000358716.4		Q9UHI6-1

Frequencies

GnomAD3 genomes

AF:

0.00000664

AC:

AN:

150634

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000658

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

GnomAD3 exomes

AF:

0.0000103

AC:

AN:

96940

Hom.:

AF XY:

0.0000186

AC XY:

AN XY:

53646

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000516

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000225

AC:

AN:

1336018

Hom.:

Cov.:

AF XY:

0.00000153

AC XY:

AN XY:

654368

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000944

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

AF:

0.00000664

AC:

AN:

150634

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

73546

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.0000658

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:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Dec 17, 2023

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.272A>T (p.K91M) alteration is located in exon 1 (coding exon 1) of the DDX20 gene. This alteration results from a A to T substitution at nucleotide position 272, causing the lysine (K) at amino acid position 91 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Uncertain

0.50

BayesDel_addAF

Benign

-0.024

BayesDel_noAF

Benign

-0.12

CADD

Pathogenic

DANN

Uncertain

1.0

DEOGEN2

Benign

0.23

Eigen

Pathogenic

0.76

Eigen_PC

Pathogenic

0.72

FATHMM_MKL

Uncertain

0.96

LIST_S2

Uncertain

0.96

M_CAP

Benign

0.048

MetaRNN

Uncertain

0.67

MetaSVM

Benign

-1.1

MutationAssessor

Benign

1.8

PrimateAI

Pathogenic

0.92

PROVEAN

Pathogenic

-4.7

REVEL

Uncertain

0.43

Sift

Uncertain

0.0040

Sift4G

Uncertain

0.0040

Polyphen

0.99

Vest4

0.65

MutPred

0.57

Loss of catalytic residue at K91 (P = 0.0273);

MVP

0.70

MPC

0.52

ClinPred

0.98

GERP RS

4.8

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.8

Varity_R

0.80

gMVP

0.74

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over