There was a significant reduction in pulmonary AT2 cell surfactant protein levels relative to sham operated animals, which developed between 1 and 3 weeks after CBDL as HPS developed (at 3 wk: SP-A 0.19±0.05 fold-control; SP-B 0.29±0.03 fold-control; pro-SP-C 0.45±0.09 fold-control, SP-D 0.50±0.12 fold-control, all p<0.05 vs sham) indicating reduced lung surfactant protein production. This evidence concerns the gene SFTPB and Hermansky-Pudlak syndrome.