rs74315431

Variant names:

• chr20-58418318-C-T
• rs74315431
• NM_004738.5:c.166C>T

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_004738.5(VAPB):​c.166C>T​(p.Pro56Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P56R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: VAPB NM_004738.5 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:7 O:1
• Conservation: PhyloP100: 7.91
• Publications: 224 publications found

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]

VAPB Gene-Disease associations (from GenCC):

• amyotrophic lateral sclerosis type 8

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen
• adult-onset proximal spinal muscular atrophy, autosomal dominant

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• amyotrophic lateral sclerosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988
• PP5: Variant 20-58418318-C-T is Pathogenic according to our data. Variant chr20-58418318-C-T is described in ClinVar as Pathogenic. ClinVar VariationId is 4806.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004738.5. 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
	VAPB	NM_004738.5	MANE Select	c.166C>T	p.Pro56Ser	missense	Exon 2 of 6	NP_004729.1	O95292-1
	VAPB	NM_001195677.2		c.166C>T	p.Pro56Ser	missense	Exon 2 of 3	NP_001182606.1	O95292-2
	VAPB	NR_036633.2		n.397C>T		non_coding_transcript_exon	Exon 2 of 4

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	VAPB	ENST00000475243.6	TSL:1 MANE Select	c.166C>T	p.Pro56Ser	missense	Exon 2 of 6	ENSP00000417175.1	O95292-1
	VAPB	ENST00000395802.7	TSL:1	c.166C>T	p.Pro56Ser	missense	Exon 2 of 3	ENSP00000379147.3	O95292-2
	VAPB	ENST00000903510.1		c.226C>T	p.Pro76Ser	missense	Exon 3 of 7	ENSP00000573569.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251468 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000163

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461886 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727244

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112010

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
3	-	-	not provided (4)
2	-	-	Amyotrophic lateral sclerosis type 8 (2)
1	-	-	Adult-onset proximal spinal muscular atrophy, autosomal dominant (1)
1	-	-	Amyotrophic lateral sclerosis type 8;C1854058:Adult-onset proximal spinal muscular atrophy, autosomal dominant (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	26
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Uncertain	0.23	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.90	D
MutationAssessor	Pathogenic	4.3	H
PhyloP100		7.9
PrimateAI	Pathogenic	0.83	D
PROVEAN	Pathogenic	-7.8	D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.96
MutPred		0.98		Gain of MoRF binding (P = 0.0517)
MVP		0.94
MPC		1.3
ClinPred		1.0	D
GERP RS		6.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.95
gMVP		0.84
Mutation Taster		=7/93	disease causing (ClinVar)

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: rs74315431; hg19: chr20-56993374;