8-99875431-G-C

Position:

• chr8-99875431-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_017890.5(VPS13B):​c.11834G>C​(p.Arg3945Pro) 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R3945Q) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: VPS13B NM_017890.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.28

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]

COX6C (HGNC:2285): (cytochrome c oxidase subunit 6C) Cytochrome c oxidase, the terminal enzyme of the mitochondrial respiratory chain, catalyzes the electron transfer from reduced cytochrome c to oxygen. It is a heteromeric complex consisting of 3 catalytic subunits encoded by mitochondrial genes and multiple structural subunits encoded by nuclear genes. The mitochondrially-encoded subunits function in electron transfer, and the nuclear-encoded subunits may be involved in the regulation and assembly of the complex. This nuclear gene encodes subunit VIc, which has 77% amino acid sequence identity with mouse subunit VIc. This gene is up-regulated in prostate cancer cells. A pseudogene has been found on chromosomes 16p12. [provided by RefSeq, Jul 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.744

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
VPS13B	NM_017890.5	c.11834G>C	p.Arg3945Pro	missense_variant	62/62	ENST00000358544.7
VPS13B	NM_152564.5	c.11759G>C	p.Arg3920Pro	missense_variant	62/62	ENST00000357162.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
VPS13B	ENST00000358544.7	c.11834G>C	p.Arg3945Pro	missense_variant	62/62	1	NM_017890.5
VPS13B	ENST00000357162.7	c.11759G>C	p.Arg3920Pro	missense_variant	62/62	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

Labcorp Genetics (formerly Invitae), Labcorp

Jul 24, 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: "Possibly 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 (ExAC no frequency). This sequence change replaces arginine with proline at codon 3945 of the VPS13B protein (p.Arg3945Pro). The arginine residue is moderately conserved and there is a moderate physicochemical difference between arginine and proline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.68
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.26
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Benign	0.13	.;T
Eigen	Pathogenic	0.77
Eigen_PC	Pathogenic	0.82
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Benign	0.066	D
MetaRNN	Pathogenic	0.74	D;D
MetaSVM	Uncertain	-0.22	T
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.57	T
PROVEAN	Benign	-1.3	N;N
REVEL	Uncertain	0.46
Sift	Benign	0.22	T;T
Sift4G	Uncertain	0.0040	D;D
Polyphen		1.0	D;D
Vest4		0.72
MutPred		0.40		.;Gain of loop (P = 0.0166);
MVP		0.87
MPC		0.37
ClinPred		0.97	D
GERP RS		5.9
Varity_R		0.21
gMVP		0.72

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: chr8-100887659;