Paroxysmal Nocturnal Hemoglobinuria 1, also known as paroxysmal nocturnal hemoglobinuria, somatic, is related to aplastic anemia and myelodysplastic syndrome. An important gene associated with Paroxysmal Nocturnal Hemoglobinuria 1 is PIGA (Phosphatidylinositol Glycan Anchor Biosynthesis Class A). Affiliated tissues include smooth muscle and bone marrow.