Mouse Anti-Human HPS4 polyclonal antibody for WB. Hermansky-Pudlak syndrome is a disorder of organelle biogenesis in which oculocutaneous albinism, bleeding, and pulmonary fibrosis result from defects of melanosomes, platelet dense granules, and lysosomes. Mutations in this gene as well as several others can cause this syndrome. The protein encoded by this gene appears to be important in organelle biogenesis and is similar to the mouse light ear protein. Multiple transcript variants encoding different isoforms have been found for this gene.