LYST and Hermansky-Pudlak syndrome: Moreover, the genetic disorder HPS caused by mutations in HPS genes and/or mutation in BLOC/s, and CHS caused by a mutation in LYST (lysosomal trafficking regulator) likely do not present phenotypes of LB dysfunction, pressing unique origin and functional mechanisms of skin LBs (Boissy and Nordlund, 1997; Dell'Angelica et al., 2000).