Additional Study Information: In some subtypes, HPS can cause breathing problems and scarring in the lungs (pulmonary fibrosis). One purpose of this research study is to learn more about lung problems in people with HPS. Another purpose of this study is to look at genes (DNA) and how they affect health and disease. Genes are the instruction manual for your body. The genes you get from your parents decide what you look like and how your body behaves. They can also tell us a persons risk for certain diseases and how they will respond to treatment. About 150 people will HPS will be a part of this study. It is hoped that if we can understand how the gene problems in HPS cause lung problems, it will eventually lead to better ways to treat pulmonary fibrosis in HPS.