Livers were collected from 7-week old mice, 3 Npc1+/+ and 3 Npc1-/- following isoflurane euthanasia and decapitation. Liver tissue was dissected, flash frozen in liquid nitrogen, and homogenized with a glass Dounce tissue grinder 25X with pestle A and 25X with pestle B) in 2 mL of EZ PREP buffer (Sigma NUC-101). Homogenized liver tissue was incubated on ice for 5 minutes, followed by an addition of 2 mL of EZ PREP, then centrifuged at 500 g for 5 minutes at 4 °C to pellet nuclei. Resulting nuclei were washed with 4 mL EZ PREP and incubated for 5 minutes on ice then centrifuged using the same parameters. Samples were washed with 4 mL nuclear suspension buffer (0.01% BSA, RNase inhibitor [Takara 2313 A]) and centrifuged using the same parameters. 1 mL of nuclear suspension buffer was added to the pellet for resuspension, then filtered with a 35 µM cell strainer (Corning 352235) and counted. Nuclei were diluted to 800-1500 cells/µL and libraries were generated with the 10X Chromium Controller system. Llibraries were generated with the 10X Chromium Controller system. Single-nucleus libraries were sequenced using the Illumina NovaSeq 6000.