10-68906852-G-C

Position:

• chr10-68906852-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_024045.2(DDX50):​c.229G>C​(p.Gly77Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,460,862 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DDX50 NM_024045.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.19

Genes affected

DDX50 (HGNC:17906): (DExD-box helicase 50) 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 DEAD box protein family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box enzyme that may be involved in ribosomal RNA synthesis or processing. This gene and DDX21, also called RH-II/GuA, have similar genomic structures and are in tandem orientation on chromosome 10, suggesting that the two genes arose by gene duplication in evolution. This gene has pseudogenes on chromosomes 2, 3 and 4. Alternative splicing of this gene generates multiple transcript variants, but the full length nature of all the other variants but one has not been defined. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.07739213).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DDX50	NM_024045.2	c.229G>C	p.Gly77Arg	missense_variant	2/15	ENST00000373585.8
DDX50	XM_011540144.3	c.34G>C	p.Gly12Arg	missense_variant	3/16
DDX50	XM_047425726.1	c.34G>C	p.Gly12Arg	missense_variant	2/15
DDX50	XM_047425727.1	c.34G>C	p.Gly12Arg	missense_variant	2/15

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DDX50	ENST00000373585.8	c.229G>C	p.Gly77Arg	missense_variant	2/15	1	NM_024045.2	P1
DDX50	ENST00000471475.1	c.*185G>C		3_prime_UTR_variant, NMD_transcript_variant	3/6	5
DDX50	ENST00000483593.5	c.*163G>C		3_prime_UTR_variant, NMD_transcript_variant	3/7	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1460862 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726672

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: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000282 Hom.: 0

Bravo AF: 0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 21, 2024

The c.229G>C (p.G77R) alteration is located in exon 2 (coding exon 2) of the DDX50 gene. This alteration results from a G to C substitution at nucleotide position 229, causing the glycine (G) at amino acid position 77 to be replaced by an arginine (R). 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	Benign	0.17
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.42
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Benign	0.045	T;T
Eigen	Benign	-0.40
Eigen_PC	Benign	-0.19
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.90	D;D
M_CAP	Benign	0.0036	T
MetaRNN	Benign	0.077	T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.7	L;.
MutationTaster	Benign	0.97	D
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-0.24	N;.
REVEL	Benign	0.068
Sift	Benign	0.16	T;.
Sift4G	Benign	0.46	T;T
Polyphen		0.053	B;.
Vest4		0.28
MutPred		0.22		Gain of solvent accessibility (P = 0.0456);.;
MVP		0.33
MPC		0.64
ClinPred		0.28	T
GERP RS		3.8
Varity_R		0.060
gMVP		0.090

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

Other links and lift over

dbSNP: rs1459877951; hg19: chr10-70666608;