rs121918386

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000384.3(APOB):​c.6253C>T​(p.Arg2085*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000155 in 1,613,848 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 Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000016 ( 0 hom. )

Consequence

APOB
NM_000384.3 stop_gained

Scores

2
3
2

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4

Conservation

PhyloP100: 2.79
Variant links:
Genes affected
APOB (HGNC:603): (apolipoprotein B) This gene product is the main apolipoprotein of chylomicrons and low density lipoproteins (LDL), and is the ligand for the LDL receptor. It occurs in plasma as two main isoforms, apoB-48 and apoB-100: the former is synthesized exclusively in the gut and the latter in the liver. The intestinal and the hepatic forms of apoB are encoded by a single gene from a single, very long mRNA. The two isoforms share a common N-terminal sequence. The shorter apoB-48 protein is produced after RNA editing of the apoB-100 transcript at residue 2180 (CAA->UAA), resulting in the creation of a stop codon, and early translation termination. Mutations in this gene or its regulatory region cause hypobetalipoproteinemia, normotriglyceridemic hypobetalipoproteinemia, and hypercholesterolemia due to ligand-defective apoB, diseases affecting plasma cholesterol and apoB levels. [provided by RefSeq, Dec 2019]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PM2
Very rare variant in population databases, with high coverage;
PP5
Variant 2-21010615-G-A is Pathogenic according to our data. Variant chr2-21010615-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 17887.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-21010615-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
APOBNM_000384.3 linkc.6253C>T p.Arg2085* stop_gained Exon 26 of 29 ENST00000233242.5 NP_000375.3 P04114Q7Z7Q0Q59HB3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
APOBENST00000233242.5 linkc.6253C>T p.Arg2085* stop_gained Exon 26 of 29 1 NM_000384.3 ENSP00000233242.1 P04114

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152056
Hom.:
0
Cov.:
33
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:
0.0000199
AC:
5
AN:
251144
Hom.:
0
AF XY:
0.0000221
AC XY:
3
AN XY:
135758
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:
0.0000352
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000164
AC:
24
AN:
1461792
Hom.:
0
Cov.:
34
AF XY:
0.0000124
AC XY:
9
AN XY:
727192
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000180
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152056
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74278
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
ExAC
AF:
0.0000412
AC:
5

ClinVar

Significance: Pathogenic/Likely pathogenic
Submissions summary: Pathogenic:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Hypercholesterolemia, autosomal dominant, type B;C4551990:Familial hypobetalipoproteinemia 1 Pathogenic:1
Mar 15, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This variant is present in population databases (rs121918386, gnomAD 0.004%). This sequence change creates a premature translational stop signal (p.Arg2085*) in the APOB gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in APOB are known to be pathogenic (PMID: 20032471). This premature translational stop signal has been observed in individual(s) with familial hypobetalipoproteinemia (PMID: 2725600). This variant is also known as C to T at nucleotide 6381. ClinVar contains an entry for this variant (Variation ID: 17887). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1
Nov 01, 2019
CeGaT Center for Human Genetics Tuebingen
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Familial hypobetalipoproteinemia Pathogenic:1
Jun 15, 1989
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Familial hypercholesterolemia Pathogenic:1
Jan 05, 2022
DASA
Significance: Likely pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The variant creates a premature translational stop signal c.6253C>T;p.(Arg2085*) in APOB gene. It is expected to result in an absent or disrupted protein product - PVS1.This variant is not present in population databases (rs121918386, gnomAD; ABraOM no frequency - http://abraom.ib.usp.br/) - PM2. In summary, the currently available evidence indicates that the variant is likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.30
D
BayesDel_noAF
Pathogenic
0.30
CADD
Pathogenic
34
DANN
Uncertain
1.0
Eigen
Uncertain
0.47
Eigen_PC
Uncertain
0.25
FATHMM_MKL
Benign
0.51
D
Vest4
0.82
GERP RS
5.1

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: rs121918386; hg19: chr2-21233487; COSMIC: COSV51924573; API