• 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

Associated disorders

The NPC1 gene is associated with autosomal recessive Niemann-Pick disease type C (MedGen UID: 465922).

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Invitae tests that include this gene:

Approximately 95% of Neimann-Pick type C cases are due to pathogenic variants in NPC1.

The NPC1 gene encodes a membrane protein believed to be localized to the late endosomal / lysosomal compartment. The exact function of the NPC1 protein is not clearly understood but it plays an important role in the intracellular sorting of cholesterol and other glycosphingolipids. Dysfunctional NPC1 protein results in impaired cholesterol homeostasis and the progressive intracellular accumulation of cholesterol and glycosphingolipids.

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
NPC1 NM_000271.4