6-31540469-C-T

Variant names:

• chr6-31540469-C-T
• rs778941682
• NM_004640.7:c.64G>A

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004640.7(DDX39B):​c.64G>A​(p.Ala22Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 14/22 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A22P) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: DDX39B NM_004640.7 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.41
• Publications: 0 publications found

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:41999): (ATP6V1G2-DDX39B readthrough (NMD candidate)) This locus represents naturally occurring read-through transcription between the neighboring ATP6V1G2 (ATPase, H+ transporting, lysosomal 13kDa, V1 subunit G2) and DDX39B (DEAD box polypeptide 39B) genes located in the major histocompatibility complex class III region of chromosome 6. The read-through transcript and is a candidate for nonsense-mediated mRNA decay (NMD), and is thus unlikely to produce a protein product. [provided by RefSeq, Feb 2011]

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.14696208).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004640.7. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DDX39B	NM_004640.7	MANE Select	c.64G>A	p.Ala22Thr	missense	Exon 2 of 11	NP_004631.1	Q13838-1
	DDX39B	NM_080598.6		c.64G>A	p.Ala22Thr	missense	Exon 2 of 11	NP_542165.1	Q13838-1
	DDX39B	NR_037852.2		n.250G>A		non_coding_transcript_exon	Exon 2 of 9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DDX39B	ENST00000396172.6	TSL:1 MANE Select	c.64G>A	p.Ala22Thr	missense	Exon 2 of 11	ENSP00000379475.1	Q13838-1
	DDX39B	ENST00000458640.5	TSL:1	c.64G>A	p.Ala22Thr	missense	Exon 2 of 11	ENSP00000416269.1	Q13838-1
	ATP6V1G2-DDX39B	ENST00000376185.5	TSL:2	n.*278G>A		non_coding_transcript_exon	Exon 4 of 13	ENSP00000365356.1	F2Z307

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Benign	-0.11	T
BayesDel_noAF	Benign	-0.39
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.0089	T
Eigen	Benign	-0.13
Eigen_PC	Benign	0.094
FATHMM_MKL	Uncertain	0.88	D
M_CAP	Benign	0.0090	T
MetaRNN	Benign	0.15	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.57	N
PhyloP100		3.4
PrimateAI	Uncertain	0.63	T
PROVEAN	Benign	-0.32	N
REVEL	Benign	0.067
Sift	Benign	0.24	T
Sift4G	Benign	0.18	T
Polyphen		0.0010	B
Vest4		0.28
MutPred		0.17		Gain of phosphorylation at A22 (P = 0.0269)
MVP		0.48
MPC		1.4
ClinPred		0.72	D
GERP RS		5.5
PromoterAI		-0.0012	Neutral
Varity_R		0.14
gMVP		0.56
Mutation Taster		=80/20	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs778941682; hg19: chr6-31508246;