Genetic Variant DDX21:p.Phe280Leu (chr10-68965430-C-G) – ACMG Classification: Likely_benign (-3 pts)

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 1P and 4B. PP3BS2

The NM_004728.4(DDX21):c.840C>G(p.Phe280Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000229 in 1,613,836 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000025 ( 0 hom. )

Consequence

DDX21
NM_004728.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.16

Variant links:

Genes affected

DDX21 (HGNC:2744): (DExD-box helicase 21) 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 is an antigen recognized by autoimmune antibodies from a patient with watermelon stomach disease. This protein unwinds double-stranded RNA, folds single-stranded RNA, and may play important roles in ribosomal RNA biogenesis, RNA editing, RNA transport, and general transcription. [provided by RefSeq, Jul 2008]

DDX21 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.785

BS2

High AC in GnomAdExome4 at 36 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DDX21	NM_004728.4 link	c.840C>G	p.Phe280Leu	missense_variant	Exon 5 of 15	ENST00000354185.9	NP_004719.2	Q9NR30-1
DDX21	NM_001410932.1 link	c.840C>G	p.Phe280Leu	missense_variant	Exon 5 of 14		NP_001397861.1
DDX21	NM_001256910.2 link	c.636C>G	p.Phe212Leu	missense_variant	Exon 5 of 15		NP_001243839.1	Q9NR30-2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DDX21	ENST00000354185.9 link	c.840C>G	p.Phe280Leu	missense_variant	Exon 5 of 15	1	NM_004728.4	ENSP00000346120.4		Q9NR30-1

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152200

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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

AF:

0.0000246

AC:

AN:

1461636

Hom.:

Cov.:

AF XY:

0.0000234

AC XY:

AN XY:

727126

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

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:

0.0000306

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152200

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74364

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

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:

0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Jul 06, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.840C>G (p.F280L) alteration is located in exon 5 (coding exon 5) of the DDX21 gene. This alteration results from a C to G substitution at nucleotide position 840, causing the phenylalanine (F) at amino acid position 280 to be replaced by a leucine (L). 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

Pathogenic

0.95

BayesDel_addAF

Uncertain

0.11

BayesDel_noAF

Uncertain

-0.080

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.26

T;.

Eigen

Benign

-0.014

Eigen_PC

Benign

0.071

FATHMM_MKL

Uncertain

0.95

LIST_S2

Uncertain

0.96

D;D

M_CAP

Benign

0.037

MetaRNN

Pathogenic

0.78

D;D

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.23

N;.

PrimateAI

Uncertain

0.74

PROVEAN

Pathogenic

-5.0

D;.

REVEL

Uncertain

0.34

Sift

Benign

0.035

D;.

Sift4G

Benign

0.074

T;T

Polyphen

0.81

P;.

Vest4

0.82

MutPred

0.55

Loss of helix (P = 0.0558);.;

MVP

0.75

MPC

1.5

ClinPred

0.98

GERP RS

4.0

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.7

Varity_R

0.87

gMVP

0.73

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

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