2-21026785-C-T

Variant summary

Our verdict is Benign. The variant received -13 ACMG points: 0P and 13B. BP4_StrongBP6BS1BS2

The NM_000384.3(APOB):​c.2244+3G>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00156 in 1,611,938 control chromosomes in the GnomAD database, including 38 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.0085 ( 18 hom., cov: 32)
Exomes 𝑓: 0.00083 ( 20 hom. )

Consequence

APOB
NM_000384.3 splice_region, intron

Scores

2
Splicing: ADA: 0.0001130
2

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1B:10

Conservation

PhyloP100: 0.659

Publications

3 publications found
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 Gene-Disease associations (from GenCC):
  • hypercholesterolemia, autosomal dominant, type B
    Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics
  • familial hypobetalipoproteinemia 1
    Inheritance: AR, AD, SD Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, ClinGen
  • homozygous familial hypercholesterolemia
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Benign. The variant received -13 ACMG points.

BP4
Computational evidence support a benign effect (BayesDel_noAF=-0.5).
BP6
Variant 2-21026785-C-T is Benign according to our data. Variant chr2-21026785-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 334167.We mark this variant Benign, oryginal submission is: [Conflicting_classifications_of_pathogenicity].
BS1
Variant frequency is greater than expected in population afr. GnomAd4 allele frequency = 0.00853 (1299/152310) while in subpopulation AFR AF = 0.0291 (1210/41556). AF 95% confidence interval is 0.0278. There are 18 homozygotes in GnomAd4. There are 657 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.
BS2
High Homozygotes in GnomAd4 at 18 AD,AR,SD gene

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
APOBNM_000384.3 linkc.2244+3G>A splice_region_variant, intron_variant Intron 15 of 28 ENST00000233242.5 NP_000375.3 P04114Q7Z7Q0Q59HB3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
APOBENST00000233242.5 linkc.2244+3G>A splice_region_variant, intron_variant Intron 15 of 28 1 NM_000384.3 ENSP00000233242.1 P04114
APOBENST00000399256.4 linkc.2244+3G>A splice_region_variant, intron_variant Intron 15 of 16 1 ENSP00000382200.4 A8MUN2
APOBENST00000673739.2 linkn.*1550+3G>A splice_region_variant, intron_variant Intron 14 of 24 ENSP00000501110.2 A0A669KB70
APOBENST00000673882.2 linkn.*1550+3G>A splice_region_variant, intron_variant Intron 14 of 22 ENSP00000501253.2 A0A669KB70

Frequencies

GnomAD3 genomes
AF:
0.00852
AC:
1297
AN:
152192
Hom.:
18
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.0292
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00452
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00316
Gnomad NFE
AF:
0.0000882
Gnomad OTH
AF:
0.00622
GnomAD2 exomes
AF:
0.00214
AC:
536
AN:
250970
AF XY:
0.00164
show subpopulations
Gnomad AFR exome
AF:
0.0290
Gnomad AMR exome
AF:
0.00130
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000618
Gnomad OTH exome
AF:
0.00163
GnomAD4 exome
AF:
0.000828
AC:
1208
AN:
1459628
Hom.:
20
Cov.:
30
AF XY:
0.000693
AC XY:
503
AN XY:
726304
show subpopulations
African (AFR)
AF:
0.0300
AC:
1003
AN:
33406
American (AMR)
AF:
0.00132
AC:
59
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26118
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39666
South Asian (SAS)
AF:
0.0000580
AC:
5
AN:
86226
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53402
Middle Eastern (MID)
AF:
0.00139
AC:
8
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000252
AC:
28
AN:
1110012
Other (OTH)
AF:
0.00174
AC:
105
AN:
60310
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.466
Heterozygous variant carriers
0
52
104
157
209
261
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Exome Hom
Variant carriers
0
34
68
102
136
170
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.00853
AC:
1299
AN:
152310
Hom.:
18
Cov.:
32
AF XY:
0.00882
AC XY:
657
AN XY:
74494
show subpopulations
African (AFR)
AF:
0.0291
AC:
1210
AN:
41556
American (AMR)
AF:
0.00451
AC:
69
AN:
15298
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4830
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10618
Middle Eastern (MID)
AF:
0.00340
AC:
1
AN:
294
European-Non Finnish (NFE)
AF:
0.0000882
AC:
6
AN:
68032
Other (OTH)
AF:
0.00616
AC:
13
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.503
Heterozygous variant carriers
0
60
120
180
240
300
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Genome Hom
Variant carriers
0
20
40
60
80
100
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.00491
Hom.:
7
Bravo
AF:
0.00944
Asia WGS
AF:
0.000866
AC:
3
AN:
3478
EpiCase
AF:
0.00
EpiControl
AF:
0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:1Benign:10
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not specified Benign:3
-
Clinical Genetics, Academic Medical Center
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Apr 09, 2025
Molecular Diagnostic Laboratory for Inherited Cardiovascular Disease, Montreal Heart Institute
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

BS1;BP6 -

not provided Benign:3
Jun 08, 2023
Quest Diagnostics Nichols Institute San Juan Capistrano
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 15, 2019
GeneDx
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Aug 08, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Familial hypobetalipoproteinemia 1 Uncertain:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This 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, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Hypercholesterolemia, autosomal dominant, type B;C4551990:Familial hypobetalipoproteinemia 1 Benign:1
Jan 30, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Hypercholesterolemia, autosomal dominant, type B Benign:1
Jan 13, 2018
Illumina Laboratory Services, Illumina
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This 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. -

Cardiovascular phenotype Benign:1
Mar 23, 2016
Ambry Genetics
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This alteration is classified as 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. -

Familial hypercholesterolemia Benign:1
Oct 11, 2022
GENinCode PLC
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
-0.50
CADD
Benign
12
DANN
Benign
0.84
PhyloP100
0.66
Mutation Taster
=59/41
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Benign
0.00011
dbscSNV1_RF
Benign
0.052
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

Other links and lift over

dbSNP: rs12714189; hg19: chr2-21249657; API