Home > Gene Browser > APOB
APOB
- Synonyms
- FCHL2, FLDB, LDLCQ4, apoB-100, apoB-48
- External resources
- NCBI338
- OMIM107730
- EnsemblENSG00000084674
- HGNCHGNC:603
- Summary
- 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.
Variant counts
The variants found in rare patients tested by 3billion are classified and counted according to ACMG guidelines. The variants with over 5% variant frequency in population genome databases ( gnomAD, dbSNP, etc) are excluded.
- Pathogenic
- 48
- Likely pathogenic
- 18
- VUS
- 6,805
- Likely benign
- 8,538
- Benign
- 5,286
Patient phenotypes
Proportions of phenotypes among 50 patients carrying pathogenic or likely pathogenic variants on APOB gene are displayed below.
- Phenotype class
- Patients in 3billion (%)
- Abnormality of the nervous system
- 42%
- Abnormality of the cardiovascular system
- 34%
- Abnormality of head or neck
- 32%
- Abnormality of the musculoskeletal system
- 28%
- Abnormality of the eye
- 24%
- Abnormality of the integument
- 24%
- Growth abnormality
- 18%
- Abnormality of the ear
- 16%
- Abnormality of limbs
- 12%
- Abnormality of the genitourinary system
- 8%
- Abnormality of blood and blood-forming tissues
- 4%
- Abnormality of the digestive system
- 4%
- Neoplasm
- 4%
- Abnormality of prenatal development or birth
- 2%
- Abnormality of the endocrine system
- 2%
- Abnormality of the immune system
- 2%
- Abnormality of the respiratory system
- 2%
- Abnormal cellular phenotype
- 0%
- Abnormality of metabolism homeostasis
- 0%
- Abnormality of the breast
- 0%
- Abnormality of the thoracic cavity
- 0%
- Abnormality of the voice
- 0%
- Constitutional symptom
- 0%
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