20-58389475-C-G

Position:

• chr20-58389475-C-G

Variant summary

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

The NM_004738.5(VAPB):​c.16C>G​(p.Gln6Glu) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts 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. Q6R) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: VAPB NM_004738.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.93

Genes affected

VAPB (HGNC:12649): (VAMP associated protein B and C) The protein encoded by this gene is a type IV membrane protein found in plasma and intracellular vesicle membranes. The encoded protein is found as a homodimer and as a heterodimer with VAPA. This protein also can interact with VAMP1 and VAMP2 and may be involved in vesicle trafficking. [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=0.23649931).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
VAPB	NM_004738.5	c.16C>G	p.Gln6Glu	missense_variant	1/6	ENST00000475243.6
VAPB	NM_001195677.2	c.16C>G	p.Gln6Glu	missense_variant	1/3
VAPB	NR_036633.2	n.247C>G		non_coding_transcript_exon_variant	1/4
VAPB	XR_001754433.3	n.247C>G		non_coding_transcript_exon_variant	1/6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
VAPB	ENST00000475243.6	c.16C>G	p.Gln6Glu	missense_variant	1/6	1	NM_004738.5	P1
VAPB	ENST00000395802.7	c.16C>G	p.Gln6Glu	missense_variant	1/3	1
VAPB	ENST00000265619.6	n.101C>G		non_coding_transcript_exon_variant	1/6	2
VAPB	ENST00000520497.1	c.16C>G	p.Gln6Glu	missense_variant, NMD_transcript_variant	1/4	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Amyotrophic lateral sclerosis type 8;C1854058:Adult-onset proximal spinal muscular atrophy, autosomal dominant Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Apr 12, 2023

An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant  is likely to be tolerated. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This variant has not been reported in the literature in individuals affected with VAPB-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glutamine, which is neutral and polar, with glutamic acid, which is acidic and polar, at codon 6 of the VAPB protein (p.Gln6Glu). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.56
BayesDel_addAF	Benign	-0.014	T
BayesDel_noAF	Benign	-0.26
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.44	T;.
Eigen	Uncertain	0.21
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Benign	0.61	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Pathogenic	0.47	D
MetaRNN	Benign	0.24	T;T
MetaSVM	Benign	-0.51	T
MutationAssessor	Uncertain	2.1	M;M
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-2.4	N;N
REVEL	Benign	0.24
Sift	Uncertain	0.0010	D;T
Sift4G	Uncertain	0.016	D;T
Polyphen		0.62	P;B
Vest4		0.43
MutPred		0.48		Loss of sheet (P = 0.0315);Loss of sheet (P = 0.0315);
MVP		0.26
MPC		0.56
ClinPred		0.90	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.77
gMVP		0.55

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: chr20-56964531;