In AT2 cells, BLOC‐3 is important for maintaining the structure of lamellar bodies through the regulation of Rab38 and of surfactant homeostasis; thus, the validation of the efficiency of cell and gene therapy in HPS‐1 melanocytes can be instrumental for the treatment of pulmonary fibrosis related to HPS. The gene discussed is HPS1; the disease is pulmonary fibrosis.