8-99013793-T-A

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_017890.5(VPS13B):c.5T>A(p.Leu2Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. L2L) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 32)
• Consequence: VPS13B NM_017890.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 7.70

Genes affected

VPS13B (HGNC:2183): (vacuolar protein sorting 13 homolog B) This gene encodes a potential transmembrane protein that may function in vesicle-mediated transport and sorting of proteins within the cell. This protein may play a role in the development and the function of the eye, hematological system, and central nervous system. Mutations in this gene have been associated with Cohen syndrome. Multiple splice variants encoding distinct isoforms have been identified for this gene. [provided by RefSeq, Jul 2008]

VPS13B-DT (HGNC:54375): (VPS13B divergent transcript)

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM1: In a domain Chorein N-terminal (size 100) in uniprot entity VP13B_HUMAN there are 6 pathogenic changes around while only 0 benign (100%) in NM_017890.5
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.888

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
VPS13B	NM_017890.5	c.5T>A	p.Leu2Gln	missense_variant	2/62	ENST00000358544.7
VPS13B	NM_152564.5	c.5T>A	p.Leu2Gln	missense_variant	2/62	ENST00000357162.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
VPS13B	ENST00000358544.7	c.5T>A	p.Leu2Gln	missense_variant	2/62	1	NM_017890.5
VPS13B	ENST00000357162.7	c.5T>A	p.Leu2Gln	missense_variant	2/62	1	NM_152564.5	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cohen syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Dec 23, 2021

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. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Not Available"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Not Available"). This variant has not been reported in the literature in individuals affected with VPS13B-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces leucine, which is neutral and non-polar, with glutamine, which is neutral and polar, at codon 2 of the VPS13B protein (p.Leu2Gln). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.37
Cadd	Pathogenic	27
Dann	Uncertain	1.0
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.72
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Uncertain	0.93	D;D;D;D
M_CAP	Uncertain	0.16	D
MetaRNN	Pathogenic	0.89	D;D;D;D
MetaSVM	Uncertain	0.67	D
MutationAssessor	Pathogenic	3.0	M;M;M;M
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-4.9	D;D;D;D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Uncertain	0.0020	D;D;D;D
Polyphen		1.0	D;D;D;D
Vest4		0.92
MutPred		0.44		Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);Loss of helix (P = 0.028);
MVP		0.98
MPC		0.55
ClinPred		1.0	D
GERP RS		4.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Varity_R		0.70
gMVP		0.74

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr8-100026021;