 When cells from patients lacking NPC1 were exposed to Ebola virus in the laboratory, the cells survived and appeared immune to the virus, further indicating that Ebola relies on NPC1 to enter cells.This might imply that genetic mutations in the NPC1 gene in humans could make some people resistant to one of the deadliest known viruses affecting humans.The same studies described similar results with Marburg virus, showing that it also needs NPC1 to enter cells.