rs769333468

Positions:

• chr15-91009799-A-T

Variant summary

Our verdict is Pathogenic. Variant got 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_018668.5(VPS33B):​c.403+2T>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000103 in 1,461,844 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000010 (0 hom.)
• Consequence: VPS33B NM_018668.5 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 7.35

Genes affected

VPS33B (HGNC:12712): (VPS33B late endosome and lysosome associated) Vesicle mediated protein sorting plays an important role in segregation of intracellular molecules into distinct organelles. Genetic studies in yeast have identified more than 40 vacuolar protein sorting (VPS) genes involved in vesicle transport to vacuoles. This gene is a member of the Sec-1 domain family, and encodes the human ortholog of rat Vps33b which is homologous to the yeast class C Vps33 protein. The mammalian class C vacuolar protein sorting proteins are predominantly associated with late endosomes/lysosomes, and like their yeast counterparts, may mediate vesicle trafficking steps in the endosome/lysosome pathway. Mutations in this gene are associated with arthrogryposis-renal dysfunction-cholestasis syndrome. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jan 2014]

ACMG classification

Verdict is Pathogenic. Variant got 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 7.8, offset of 16, new splice context is: aatGTgagt. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 15-91009799-A-T is Pathogenic according to our data. Variant chr15-91009799-A-T is described in ClinVar as [Pathogenic]. Clinvar id is 317430.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr15-91009799-A-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
VPS33B	NM_018668.5	c.403+2T>A		splice_donor_variant		ENST00000333371.8	NP_061138.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
VPS33B	ENST00000333371.8	c.403+2T>A		splice_donor_variant		1	NM_018668.5	ENSP00000327650	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000199 AC: 5 AN: 251458 Hom.: 0 AF XY: 0.0000221 AC XY: 3 AN XY: 135900

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.000272

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000103 AC: 15 AN: 1461844 Hom.: 0 Cov.: 31 AF XY: 0.00000963 AC XY: 7 AN XY: 727220

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.000378

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ExAC AF: 0.0000247 AC: 3

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Arthrogryposis, renal dysfunction, and cholestasis 1 Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Apr 27, 2017	- -
Pathogenic, no assertion criteria provided	literature only	OMIM	Aug 18, 2022	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.42	D
BayesDel_noAF	Pathogenic	0.33
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	0.99	D
MutationTaster	Benign	1.0	D;D;D
GERP RS		5.8
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.97		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.37		Position offset: -14
DS_DL_spliceai		0.97		Position offset: 2

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

Publications

LitVar

Other links and lift over

dbSNP: rs769333468; hg19: chr15-91553029;