15-91005053-A-G

Variant names:

• chr15-91005053-A-G
• rs753008447
• NM_018668.5:c.1170+2T>C

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_018668.5(VPS33B):​c.1170+2T>C variant causes a splice donor, intron change. The variant was absent in control chromosomes in GnomAD project. 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 Uncertain significance (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: VPS33B NM_018668.5 splice_donor, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 6.16
• Publications: 0 publications found

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]

ENSG00000284946 (HGNC:):

VPS33B-DT (HGNC:51413): (VPS33B divergent transcript)

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 4.4, offset of 44, new splice context is: gagGTgggg. 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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
VPS33B	NM_018668.5	c.1170+2T>C		splice_donor_variant, intron_variant	Intron 15 of 22	ENST00000333371.8	NP_061138.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
VPS33B	ENST00000333371.8	c.1170+2T>C		splice_donor_variant, intron_variant	Intron 15 of 22	1	NM_018668.5	ENSP00000327650.4
ENSG00000284946	ENST00000643536.1	n.1170+2T>C		splice_donor_variant, intron_variant	Intron 15 of 34			ENSP00000494429.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: no assertion criteria provided

Submissions by phenotype

not provided Uncertain:1

Sep 16, 2018

Gharavi Laboratory, Columbia University

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: research

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.020
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.0	.;.
Eigen	Pathogenic	0.94
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.0	.;.
MetaRNN	Benign	0.0	.;.
MutationAssessor	Benign	0.0	.;.
PhyloP100		6.2
PROVEAN	Benign	0.0	.;.
REVEL	Benign	0.0
Sift	Pathogenic	0.0	.;.
Sift4G	Pathogenic	0.0	.;.
Vest4		0.0
GERP RS		5.1
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	0.86
SpliceAI score (max)		0.95		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.26		Position offset: -6
DS_DL_spliceai		0.95		Position offset: 2

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

Other links and lift over

dbSNP: rs753008447; hg19: chr15-91548283;