6-31540441-G-A

Position:

• chr6-31540441-G-A

Variant summary

Our verdict is Likely benign. Variant got -4 ACMG points: 2P and 6B. PM2 BP4_Moderate BS2

The NM_004640.7(DDX39B):​c.92C>T​(p.Ala31Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,890 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict 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. A31P) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: DDX39B NM_004640.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.48

Genes affected

DDX39B (HGNC:13917): (DExD-box helicase 39B) This gene encodes a member of the DEAD box family of RNA-dependent ATPases that mediate ATP hydrolysis during pre-mRNA splicing. The encoded protein is an essential splicing factor required for association of U2 small nuclear ribonucleoprotein with pre-mRNA, and it also plays an important role in mRNA export from the nucleus to the cytoplasm. This gene belongs to a cluster of genes localized in the vicinity of the genes encoding tumor necrosis factor alpha and tumor necrosis factor beta. These genes are all within the human major histocompatibility complex class III region. Mutations in this gene may be associated with rheumatoid arthritis. Alternative splicing results in multiple transcript variants. Related pseudogenes have been identified on both chromosomes 6 and 11. Read-through transcription also occurs between this gene and the upstream ATP6V1G2 (ATPase, H+ transporting, lysosomal 13kDa, V1 subunit G2) gene. [provided by RefSeq, Feb 2011]

ATP6V1G2-DDX39B (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.15031943).
• BS2: High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
DDX39B	NM_004640.7	c.92C>T	p.Ala31Val	missense_variant	2/11	ENST00000396172.6
ATP6V1G2-DDX39B	NR_037853.1	n.895C>T		non_coding_transcript_exon_variant	4/13
DDX39B	NM_080598.6	c.92C>T	p.Ala31Val	missense_variant	2/11
DDX39B	NR_037852.2	n.278C>T		non_coding_transcript_exon_variant	2/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
DDX39B	ENST00000396172.6	c.92C>T	p.Ala31Val	missense_variant	2/11	1	NM_004640.7	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461890 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727246

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: 0.00000450

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

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

Dec 31, 2023

The c.92C>T (p.A31V) alteration is located in exon 2 (coding exon 1) of the DDX39B gene. This alteration results from a C to T substitution at nucleotide position 92, causing the alanine (A) at amino acid position 31 to be replaced by a valine (V). 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	0.078
BayesDel_addAF	Benign	-0.11	T
BayesDel_noAF	Benign	-0.39
CADD	Uncertain	24
DANN	Uncertain	1.0
DEOGEN2	Benign	0.023	T;T;T;.;.;.;T;.;T;T;.;T
Eigen	Benign	-0.21
Eigen_PC	Benign	0.037
FATHMM_MKL	Uncertain	0.85	D
M_CAP	Benign	0.0062	T
MetaRNN	Benign	0.15	T;T;T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.1	.;L;L;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D;D;D;N;N
PrimateAI	Uncertain	0.62	T
PROVEAN	Benign	-1.1	N;N;N;N;N;N;N;N;N;N;N;N
REVEL	Benign	0.035
Sift	Benign	0.17	T;T;T;T;T;T;T;T;T;T;T;T
Sift4G	Benign	0.26	T;T;T;T;T;.;.;T;.;.;.;.
Polyphen		0.0020	B;B;B;.;.;.;.;.;.;.;.;.
Vest4		0.064
MutPred		0.18		Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);Gain of methylation at K32 (P = 0.0475);.;Gain of methylation at K32 (P = 0.0475);.;Gain of methylation at K32 (P = 0.0475);
MVP		0.38
MPC		1.5
ClinPred		0.42	T
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.15
gMVP		0.47

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs375215990; hg19: chr6-31508218;