chr2-21038062-G-C

Variant names:

• chr2-21038062-G-C
• rs6752026
• NM_000384.3:c.433C>G

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_000384.3(APOB):​c.433C>G​(p.Pro145Ala) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,878 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P145Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: APOB NM_000384.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.03
• Publications: 18 publications found

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: ClinGen, Genomics England PanelApp, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• familial hypobetalipoproteinemia 1

  Inheritance: AR, SD, AD Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), ClinGen, Genomics England PanelApp
• homozygous familial hypercholesterolemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000384.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APOB	NM_000384.3	MANE Select	c.433C>G	p.Pro145Ala	missense	Exon 5 of 29	NP_000375.3	P04114

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APOB	ENST00000233242.5	TSL:1 MANE Select	c.433C>G	p.Pro145Ala	missense	Exon 5 of 29	ENSP00000233242.1	P04114
	APOB	ENST00000399256.4	TSL:1	c.433C>G	p.Pro145Ala	missense	Exon 5 of 17	ENSP00000382200.4	A8MUN2
	APOB	ENST00000673739.2		n.384-807C>G		intron	N/A	ENSP00000501110.2	A0A669KB70

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD2 exomes AF: 0.00000795 AC: 2 AN: 251488 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461878 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727248

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000504 AC: 2 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53420

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112002

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Hypercholesterolemia, autosomal dominant, type B;C4551990:Familial hypobetalipoproteinemia 1 (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.16	T
BayesDel_noAF	Benign	-0.30
CADD	Uncertain	24
DANN	Uncertain	0.99
DEOGEN2	Benign	0.16	T
Eigen	Pathogenic	0.70
Eigen_PC	Uncertain	0.66
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.81	T
M_CAP	Benign	0.017	T
MetaRNN	Uncertain	0.47	T
MetaSVM	Benign	-0.76	T
PhyloP100		5.0
PrimateAI	Benign	0.41	T
PROVEAN	Pathogenic	-4.6	D
REVEL	Benign	0.21
Sift	Benign	0.071	T
Sift4G	Benign	0.22	T
Vest4		0.50
MutPred		0.56		Loss of glycosylation at P145 (P = 0.0721)
MVP		0.72
MPC		0.14
ClinPred		0.96	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
gMVP		0.71
Mutation Taster		=58/42	polymorphism

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

Other links and lift over

dbSNP: rs6752026; hg19: chr2-21260934;