rs63750652

Positions:

• chr3-87253711-G-A
• chr3-87253711-G-C

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The ENST00000263780.9(CHMP2B):​c.532-1G>A variant causes a splice acceptor 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as not provided (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: CHMP2B ENST00000263780.9 splice_acceptor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: not provided no classification provided O:1
• Conservation: PhyloP100: 9.12

Genes affected

CHMP2B (HGNC:24537): (charged multivesicular body protein 2B) This gene encodes a component of the heteromeric ESCRT-III complex (Endosomal Sorting Complex Required for Transport III) that functions in the recycling or degradation of cell surface receptors. ESCRT-III functions in the concentration and invagination of ubiquitinated endosomal cargos into intralumenal vesicles. The protein encoded by this gene is found as a monomer in the cytosol or as an oligomer in ESCRT-III complexes on endosomal membranes. It is expressed in neurons of all major regions of the brain. Mutations in this gene result in one form of familial frontotemporal lobar degeneration. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 2.8722742 fraction of the gene. Cryptic splice site detected, with MaxEntScore 5.4, offset of -48, new splice context is: gcacatcctgtatgtcctAGtcc. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CHMP2B	NM_014043.4	c.532-1G>A		splice_acceptor_variant		ENST00000263780.9	NP_054762.2
CHMP2B	NM_001244644.2	c.409-1G>A		splice_acceptor_variant			NP_001231573.1
CHMP2B	NM_001410777.1	c.628-1G>A		splice_acceptor_variant			NP_001397706.1
CHMP2B	XM_011533576.3	c.580-1G>A		splice_acceptor_variant			XP_011531878.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CHMP2B	ENST00000263780.9	c.532-1G>A		splice_acceptor_variant		1	NM_014043.4	ENSP00000263780	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: not provided

Submissions summary: Other:1

Revision: no classification provided

Submissions by phenotype

Frontotemporal dementia and/or amyotrophic lateral sclerosis 7 Other:1

not provided, no classification provided

literature only

GeneReviews

-

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
MutationTaster	Benign	1.0	D;D;D
GERP RS		5.8

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.96		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.21		Position offset: 11
DS_AL_spliceai		0.96		Position offset: 1

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

Publications

LitVar

Other links and lift over

dbSNP: rs63750652; hg19: chr3-87302861;