12-6464504-G-T

Variant names:

• chr12-6464504-G-T
• rs1949954642
• ENST00000361716.8:c.*372C>A

Variant summary

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

The NM_014231.5(VAMP1):​c.341-18C>A variant causes a intron 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. Variant has been reported in ClinVar as Uncertain significance (★). There are indicators that this mutation may affect the branch point..

• Frequency: Genomes: not found (cov: 32)
• Consequence: VAMP1 NM_014231.5 intron
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.85
• Publications: 0 publications found

Genes affected

VAMP1 (HGNC:12642): (vesicle associated membrane protein 1) Synapotobrevins, syntaxins, and the synaptosomal-associated protein SNAP25 are the main components of a protein complex involved in the docking and/or fusion of synaptic vesicles with the presynaptic membrane. The protein encoded by this gene is a member of the vesicle-associated membrane protein (VAMP)/synaptobrevin family. Mutations in this gene are associated with autosomal dominant spastic ataxia 1. Multiple alternative splice variants have been described, but the full-length nature of some variants has not been defined. [provided by RefSeq, Jul 2014]

TAPBPL (HGNC:30683): (TAP binding protein like) Tapasin, or TAPBP (MIM 601962), is a member of the variable-constant Ig superfamily that links major histocompatibility complex (MHC) class I molecules to the transporter associated with antigen processing (TAP; see MIM 170260) in the endoplasmic reticulum (ER). The TAPBP gene is located near the MHC complex on chromosome 6p21.3. TAPBPL is a member of the Ig superfamily that is localized on chromosome 12p13.3, a region somewhat paralogous to the MHC.[supplied by OMIM, Mar 2008]

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
VAMP1	NM_014231.5	c.341-18C>A		intron_variant	Intron 4 of 4	ENST00000396308.4	NP_055046.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
VAMP1	ENST00000396308.4	c.341-18C>A		intron_variant	Intron 4 of 4	2	NM_014231.5	ENSP00000379602.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 34

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic paraplegia Uncertain:1

Sep 19, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with VAMP1-related conditions. ClinVar contains an entry for this variant (Variation ID: 2031551). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. 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 sequence change falls in intron 4 of the VAMP1 gene. It does not directly change the encoded amino acid sequence of the VAMP1 protein. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.26
CADD	Benign	16
DANN	Benign	0.89
PhyloP100		1.9
La Branchor		0.32
BranchPoint Hunter		3.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		0.95

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.35		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.35		Position offset: -18

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

Other links and lift over

dbSNP: rs1949954642; hg19: chr12-6573670;