Niemann-Pick type C (NPC) is a lysosomal storage disease associated with mutations in NPC1 and NPC2 genes. Niemann-Pick Type C strikes an estimated 1:150,000 people. The clinical manifestations of types Niemann Pick Type C1 and C2 are similar because the respective genes are both involved in egress of lipids, particularly cholesterol, from late endosomes or lysosomes. Four types of Niemann-Pick disease have been classified: the classic infantile form type A, the visceral form type B, the subacute or juvenile form type C, and the Nova Scotian variant type D. We provide sequencing analysis for the genes listed below that are associated with NPC.
Type D (Nova Scotian type)
||The NPC1 gene encodes a protein that is located in membranes inside the cell and is involved in the movement of cholesterol and lipids within cells. A deficiency of this protein leads to the abnormal build up of lipids and cholesterol within cell membranes. 95% of cases caused by mutation in this gene.
The NPC2 gene encodes a protein that binds and transports cholesterol. It has been shown to closely interact with NPC1. 5% of cases associated with mutation of this gene.
Methodology: Sequencing of entire coding region
Purpose: Confirmation of Clinical Diagnosis
ICD-10 code E75.249
Test Requisition: Sequencing Requisition
NPC1 CPT Code: 81406 Cost: $1100.00
NPC2 CPT Code: 81404 Cost: $1100.00
Panel CPT Codes: 81406, 81404 Cost: $2200.00
Turn-around-time: 5-6 weeks for each test
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