2-21033498-C-T

Position:

chr2-21033498-C-T

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 2P and 3B. PM2BP4_ModerateBP6

The NM_000384.3(APOB):c.925G>A(p.Ala309Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000268 in 1,613,926 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A309S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00022 ( 0 hom., cov: 32)

Exomes 𝑓: 0.00027 ( 0 hom. )

Consequence

APOB
NM_000384.3 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:3B:2

Conservation

PhyloP100: 0.708

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]

APOB links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (MetaRNN=0.12785399).

BP6

Variant 2-21033498-C-T is Benign according to our data. Variant chr2-21033498-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 544069.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=3}. Variant chr2-21033498-C-T is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
APOB	NM_000384.3 linkuse as main transcript	c.925G>A	p.Ala309Thr	missense_variant	9/29	ENST00000233242.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
APOB	ENST00000233242.5 linkuse as main transcript	c.925G>A	p.Ala309Thr	missense_variant	9/29	1	NM_000384.3	P1
APOB	ENST00000399256.4 linkuse as main transcript	c.925G>A	p.Ala309Thr	missense_variant	9/17	1
APOB	ENST00000673739.2 linkuse as main transcript	c.*231G>A		3_prime_UTR_variant, NMD_transcript_variant	8/25
APOB	ENST00000673882.2 linkuse as main transcript	c.*231G>A		3_prime_UTR_variant, NMD_transcript_variant	8/23

Frequencies

GnomAD3 genomes

AF:

0.000224

AC:

AN:

152100

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000290

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:

0.000309

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.000211

AC:

AN:

251452

Hom.:

AF XY:

0.000191

AC XY:

AN XY:

135902

show subpopulations

Gnomad AFR exome

AF:

0.000308

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.0000992

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.0000462

Gnomad NFE exome

AF:

0.000396

Gnomad OTH exome

AF:

0.000163

GnomAD4 exome

AF:

0.000273

AC:

399

AN:

1461826

Hom.:

Cov.:

AF XY:

0.000246

AC XY:

179

AN XY:

727220

show subpopulations

Gnomad4 AFR exome

AF:

0.000239

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000504

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.000169

Gnomad4 NFE exome

AF:

0.000329

Gnomad4 OTH exome

AF:

0.000215

GnomAD4 genome

AF:

0.000224

AC:

AN:

152100

Hom.:

Cov.:

AF XY:

0.000202

AC XY:

AN XY:

74276

show subpopulations

Gnomad4 AFR

AF:

0.000290

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:

0.000309

Gnomad4 OTH

AF:

0.000478

Alfa

AF:

0.000309

Hom.:

Bravo

AF:

0.000200

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.000233

AC:

ExAC

AF:

0.000247

AC:

EpiCase

AF:

0.000545

EpiControl

AF:

0.000474

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:3Benign:2

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Apr 01, 2021	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Jan 09, 2020	- -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Feb 18, 2021

DNA sequence analysis of the APOB gene demonstrated a sequence change, c.925G>A, in exon 9 that results in an amino acid change, p.Ala309Thr. This sequence change has been described in gnomAD with a low population frequency of 0.022% (dbSNP rs141888564). The p.Ala309Thr change affects a moderately conserved amino acid residue located in a domain of the APOB protein that is known to be functional. The p.Ala309Thr substitution appears to be benign using several in-silico pathogenicity prediction tools (SIFT, PolyPhen2, Align GVGD, REVEL). This sequence change does not appear to have been previously described in patients with APOB-related disorders. Due to the lack of sufficient evidences, the clinical significance of the p.Ala309Thr change remains unknown at this time. -

Hypercholesterolemia, autosomal dominant, type B;C4551990:Familial hypobetalipoproteinemia 1

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Feb 01, 2024

- -

Cardiovascular phenotype

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 13, 2022

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.088

BayesDel_addAF

Benign

-0.43

BayesDel_noAF

Benign

-0.54

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.020

.;T

Eigen

Benign

0.029

Eigen_PC

Benign

-0.015

FATHMM_MKL

Benign

0.58

LIST_S2

Benign

0.72

.;T

M_CAP

Benign

0.023

MetaRNN

Benign

0.13

T;T

MetaSVM

Benign

-0.94

MutationTaster

Benign

0.79

N;N

PrimateAI

Benign

0.31

PROVEAN

Benign

-1.7

N;N

REVEL

Benign

0.13

Sift

Benign

0.17

T;T

Sift4G

Uncertain

0.0020

D;D

Vest4

0.094

MVP

0.63

MPC

0.048

ClinPred

0.070

GERP RS

3.7

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.0

gMVP

0.34

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over