BLOC1S3 and Hermansky-Pudlak syndrome: All over the world, a total of eleven types of HPS have been reported that are caused by mutations in AP-3, BLOC-1, BLOC-2, and BLOC-3 protein complexes, while from Pakistan, only three reports have been made so far that reported HPS1, HPS3, HPS4, HPS6, HPS8, and HPS9 types.