13-48233415-G-A

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 0P and 6B. BP4_ModerateBS2

The NM_021999.5(ITM2B):​c.55G>A​(p.Glu19Lys) variant causes a missense change. The variant allele was found at a frequency of 0.000009 in 1,554,836 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)
Exomes 𝑓: 0.0000093 ( 0 hom. )

Consequence

ITM2B
NM_021999.5 missense

Scores

3
16

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 5.42
Variant links:
Genes affected
ITM2B (HGNC:6174): (integral membrane protein 2B) Amyloid precursor proteins are processed by beta-secretase and gamma-secretase to produce beta-amyloid peptides which form the characteristic plaques of Alzheimer disease. This gene encodes a transmembrane protein which is processed at the C-terminus by furin or furin-like proteases to produce a small secreted peptide which inhibits the deposition of beta-amyloid. Mutations which result in extension of the C-terminal end of the encoded protein, thereby increasing the size of the secreted peptide, are associated with two neurogenerative diseases, familial British dementia and familial Danish dementia. [provided by RefSeq, Oct 2009]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.13096309).
BS2
High AC in GnomAdExome4 at 13 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
ITM2BNM_021999.5 linkuse as main transcriptc.55G>A p.Glu19Lys missense_variant 1/6 ENST00000647800.2 NP_068839.1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
ITM2BENST00000647800.2 linkuse as main transcriptc.55G>A p.Glu19Lys missense_variant 1/6 NM_021999.5 ENSP00000497221.1 Q9Y287-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152126
Hom.:
0
Cov.:
31
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000303
AC:
5
AN:
165076
Hom.:
0
AF XY:
0.0000332
AC XY:
3
AN XY:
90356
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000708
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000927
AC:
13
AN:
1402710
Hom.:
0
Cov.:
30
AF XY:
0.00000864
AC XY:
6
AN XY:
694604
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.0000127
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000111
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152126
Hom.:
0
Cov.:
31
AF XY:
0.0000135
AC XY:
1
AN XY:
74316
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000665
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000511
AC:
6

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Uncertain significance, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpNov 02, 2022The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This sequence change replaces glutamic acid, which is acidic and polar, with lysine, which is basic and polar, at codon 19 of the ITM2B protein (p.Glu19Lys). This variant has not been reported in the literature in individuals affected with ITM2B-related conditions. 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: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). ClinVar contains an entry for this variant (Variation ID: 1400286). -
Uncertain significance, criteria provided, single submitterclinical testingClinical Genetics Laboratory, Skane University Hospital LundNov 10, 2022- -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJul 27, 2023Variant summary: ITM2B c.55G>A (p.Glu19Lys) results in a conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 3e-05 in 165076 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.55G>A in individuals affected with ITM2B-Related Disorders and no experimental evidence demonstrating its impact on protein function have been reported. One submitter has cited clinical-significance assessments for this variant to ClinVar after 2014 and has classified the variant as uncertain significance. Based on the evidence outlined above, the variant was classified as uncertain significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.12
BayesDel_addAF
Benign
-0.15
T
BayesDel_noAF
Benign
-0.46
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Benign
0.15
T;.;T
Eigen
Benign
-0.075
Eigen_PC
Benign
0.12
FATHMM_MKL
Uncertain
0.91
D
LIST_S2
Benign
0.72
.;T;T
M_CAP
Benign
0.048
D
MetaRNN
Benign
0.13
T;T;T
MetaSVM
Benign
-1.1
T
MutationAssessor
Benign
1.0
L;L;L
PrimateAI
Uncertain
0.77
T
PROVEAN
Benign
-1.2
N;N;.
REVEL
Benign
0.016
Sift
Benign
0.40
T;D;.
Sift4G
Benign
0.89
T;T;.
Polyphen
0.0020
B;.;B
Vest4
0.23
MVP
0.17
MPC
0.47
ClinPred
0.18
T
GERP RS
5.0
Varity_R
0.20
gMVP
0.45

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

LitVar

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

Other links and lift over

dbSNP: rs772385941; hg19: chr13-48807551; API