NPC intracellular cholesterol transporter 1
The NPC1 gene provides instructions for making a protein that is located within the membrane of compartments in the cell called lysosomes and endosomes, which digest and recycle materials. While the exact function of this protein is unclear, it plays a role in the movement of cholesterol and other types of fats (lipids) within cells and across cell membranes.
More than 380 mutations in the NPC1 gene have been found to cause Niemann-Pick disease type C1. This type of Niemann-Pick disease is characterized by a buildup of fat within cells that leads to movement problems, neurological impairment, lung and liver disease, and speech and feeding problems. Many of the NPC1 gene mutations result in a change in a single protein building block (amino acid) in the NPC1 protein. These mutations usually cause a shortage of functional protein, which prevents movement of cholesterol and other lipids, leading to their accumulation in cells. Because these lipids are not in their proper location in cells, many normal cell functions that require lipids (such as cell membrane formation) are impaired. The accumulation of lipids and the cell dysfunction eventually leads to cell death, causing the tissue and organ damage seen in Niemann-Pick disease type C1.
- Niemann-Pick disease, type C1