11-118754770-T-A

Position:

• chr11-118754770-T-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP2 PP3

The NM_004397.6(DDX6):​c.1394A>T​(p.Asp465Val) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,504 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: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: DDX6 NM_004397.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 8.02

Genes affected

DDX6 (HGNC:2747): (DEAD-box helicase 6) This gene encodes a member of the DEAD box protein family. The protein is an RNA helicase found in P-bodies and stress granules, and functions in translation suppression and mRNA degradation. It is required for microRNA-induced gene silencing. Multiple alternatively spliced variants, encoding the same protein, have been identified. [provided by RefSeq, Mar 2012]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a domain Helicase C-terminal (size 160) in uniprot entity DDX6_HUMAN there are 8 pathogenic changes around while only 0 benign (100%) in NM_004397.6
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), DDX6. . Trascript score misZ 4.2715 (greater than threshold 3.09). GenCC has associacion of gene with intellectual disability, autosomal dominant 40, syndromic intellectual disability, intellectual developmental disorder with impaired language and dysmorphic facies.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.829

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DDX6	NM_004397.6	c.1394A>T	p.Asp465Val	missense_variant	13/14	ENST00000534980.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DDX6	ENST00000534980.7	c.1394A>T	p.Asp465Val	missense_variant	13/14	1	NM_004397.6	P1
DDX6	ENST00000526070.2	c.1394A>T	p.Asp465Val	missense_variant	13/13	1		P1
DDX6	ENST00000620157.4	c.1394A>T	p.Asp465Val	missense_variant	13/14	1		P1
DDX6	ENST00000529162.1	n.997A>T		non_coding_transcript_exon_variant	5/6	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461504 Hom.: 0 Cov.: 30 AF XY: 0.00000138 AC XY: 1 AN XY: 727054

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: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Intellectual developmental disorder with impaired language and dysmorphic facies Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Jun 24, 2022

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as VUS-3A. Following criteria are met: 0105 - The mechanism of disease for this gene is not clearly established. Dominant-negative has been suggested as a likely disease mechanism (PMID: 31422817). (I) 0107 - This gene is associated with autosomal dominant disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from aspartic acid to valine. (I) 0251 - This variant is heterozygous. (I) 0301 - Variant is absent from gnomAD (both v2 and v3). (SP) 0501 - Missense variant consistently predicted to be conflicting by multiple in silico tools and highly conserved with a major amino acid change. (SP) 0603 - Missense variant in a region that is highly intolerant to missense variation (high constraint region in gnomAD). (SP) 0705 - No comparable missense variants have previous evidence for pathogenicity. (I) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.56
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.11
CADD	Pathogenic	32
DANN	Uncertain	0.99
DEOGEN2	Benign	0.25	T;T;T
Eigen	Pathogenic	0.71
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D;.;.
M_CAP	Uncertain	0.090	D
MetaRNN	Pathogenic	0.83	D;D;D
MetaSVM	Benign	-0.90	T
MutationAssessor	Benign	1.2	L;L;L
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Pathogenic	0.87	D
PROVEAN	Pathogenic	-8.6	.;D;D
REVEL	Uncertain	0.64
Sift	Pathogenic	0.0	.;D;D
Sift4G	Uncertain	0.0020	D;D;D
Polyphen		1.0	D;D;D
Vest4		0.83
MutPred		0.45		Gain of methylation at K466 (P = 0.0264);Gain of methylation at K466 (P = 0.0264);Gain of methylation at K466 (P = 0.0264);
MVP		0.83
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.92
gMVP		0.95

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr11-118625479;