Erythrocytosis, Familial, 3, also known as ecyt3, is related to autosomal dominant secondary polycythemia and duodenal somatostatinoma. An important gene associated with Erythrocytosis, Familial, 3 is EGLN1 (Egl-9 Family Hypoxia Inducible Factor 1), and among its related pathways/superpathways are Cellular responses to stimuli and Translational Control. Affiliated tissues include bone marrow and bone, and related phenotypes are increased hematocrit and increased hemoglobin