chr3-87240728-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 4P and 4B. PVS1_StrongBS2

The NM_014043.4(CHMP2B):​c.64C>T​(p.Arg22Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000153 in 1,612,998 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.00012 ( 0 hom., cov: 32)
Exomes 𝑓: 0.00016 ( 0 hom. )

Consequence

CHMP2B
NM_014043.4 stop_gained

Scores

4
2
1

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:2

Conservation

PhyloP100: 3.02
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PVS1
Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 4 pathogenic variants in the truncated region.
BS2
High AC in GnomAd4 at 18 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CHMP2BNM_014043.4 linkuse as main transcriptc.64C>T p.Arg22Ter stop_gained 2/6 ENST00000263780.9 NP_054762.2
CHMP2BNM_001410777.1 linkuse as main transcriptc.160C>T p.Arg54Ter stop_gained 3/7 NP_001397706.1
CHMP2BXM_011533576.3 linkuse as main transcriptc.112C>T p.Arg38Ter stop_gained 2/6 XP_011531878.1
CHMP2BNM_001244644.2 linkuse as main transcriptc.4-4986C>T intron_variant NP_001231573.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CHMP2BENST00000263780.9 linkuse as main transcriptc.64C>T p.Arg22Ter stop_gained 2/61 NM_014043.4 ENSP00000263780 P1Q9UQN3-1

Frequencies

GnomAD3 genomes
AF:
0.000118
AC:
18
AN:
151974
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00432
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.000271
AC:
68
AN:
251198
Hom.:
0
AF XY:
0.000273
AC XY:
37
AN XY:
135750
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00526
Gnomad EAS exome
AF:
0.0000544
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000969
Gnomad OTH exome
AF:
0.000326
GnomAD4 exome
AF:
0.000156
AC:
228
AN:
1461024
Hom.:
0
Cov.:
29
AF XY:
0.000169
AC XY:
123
AN XY:
726868
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00605
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000378
Gnomad4 OTH exome
AF:
0.000431
GnomAD4 genome
AF:
0.000118
AC:
18
AN:
151974
Hom.:
0
Cov.:
32
AF XY:
0.0000539
AC XY:
4
AN XY:
74194
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00432
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000441
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.000306
Hom.:
0
Bravo
AF:
0.000193
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.000231
AC:
28
EpiCase
AF:
0.000164
EpiControl
AF:
0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:2
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Frontotemporal dementia and/or amyotrophic lateral sclerosis 7 Benign:2
Likely benign, criteria provided, single submitterclinical testingIllumina Laboratory Services, IlluminaSep 12, 2017This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -
Likely benign, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpSep 27, 2023- -
CHMP2B-related disorder Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingPreventionGenetics, part of Exact SciencesSep 12, 2023The CHMP2B c.64C>T variant is predicted to result in premature protein termination (p.Arg22*). While this variant has been reported in one individual with frontotemporal dementia (Ramos et al. 2020. PubMed ID: 31914217), in gnomAD, it is present at an elevated frequency in older individuals not known to be affected by neurodegeneration. Specifically, this variant is reported in 0.53% of alleles in individuals of Ashkenazi Jewish descent in gnomAD (http://gnomad.broadinstitute.org/variant/3-87289878-C-T). Although we suspect this variant may be benign, at this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingGeneDxSep 26, 2019Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss-of-function is not a known mechanism of disease; Has not been previously published as pathogenic or benign to our knowledge; This variant is associated with the following publications: (PMID: 31914217) -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.50
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
39
DANN
Uncertain
1.0
Eigen
Pathogenic
0.84
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Uncertain
0.86
D
MutationTaster
Benign
1.0
A;A;D
Vest4
0.85
GERP RS
5.5
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.7

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs138886714; hg19: chr3-87289878; COSMIC: COSV99773312; API