• Turnaround time:
    10–21 calendar days (14 days on average)
  • Preferred specimen:
    3mL whole blood in a purple-top tube
  • Alternate specimens:
    DNA or saliva/assisted saliva
  • Sample requirements
  • Request a sample kit



FLDB; LDLCQ4; apoB-100; apoB-48

Associated disorders

The APOB gene is associated with autosomal dominant familial hypercholesterolemia (FH) (MedGen UID: 309962) and familial hypobetalipoproteinemia (FHBL) (MedGen UID: 775747). Generally the presence of two pathogenic variants for either condition is associated with severe forms commonly referred to as homozygous FH (HoFH) (MedGen UID: 468437) and homozygous FHBL (Ho-FHBL), respectively.

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Invitae tests that include this gene:

Pathogenic APOB variants are associated with 1%-5% of clinical cases of familial hypercholesterolemia and an unknown percentage of cases of familial hypobetalipoproteinemia.

The APOB gene encodes the apolipoprotein B protein. This protein is part of the lipoprotein complex, which consists of proteins that carry fats and cholesterol in the blood. Pathogenic variants in genes encoding lipoproteins are a common cause of inherited lipidemias.

Assay and technical information

Invitae is a College of American Pathologists (CAP)-accredited and Clinical Laboratory Improvement Amendments (CLIA)-certified clinical diagnostic laboratory performing full-gene sequencing and deletion/duplication analysis using next-generation sequencing technology (NGS).

Our sequence analysis covers clinically important regions of each gene, including coding exons, +/- 10 base pairs of adjacent intronic sequence, and select noncoding variants. Our assay provides a Q30 quality-adjusted mean coverage depth of 350x (50x minimum, or supplemented with additional analysis). Variants classified as pathogenic or likely pathogenic are confirmed with orthogonal methods, except individual variants that have high quality scores and previously validated in at least ten unrelated samples.

Our analysis detects most intragenic deletions and duplications at single exon resolution. However, in rare situations, single-exon copy number events may not be analyzed due to inherent sequence properties or isolated reduction in data quality. If you are requesting the detection of a specific single-exon copy number variation, please contact Client Services before placing your order.

Gene Transcript reference Sequencing analysis Deletion/Duplication analysis
APOB NM_000384.2