Protein S Deficiency, also known as hereditary thrombophilia due to protein s deficiency, is related to vitamin k deficiency bleeding and esophageal varix. An important gene associated with Protein S Deficiency is PROS1 (Protein S), and among its related pathways/superpathways are Metabolism of proteins and Response to elevated platelet cytosolic Ca2+. Affiliated tissues include skin and endothelial, and related phenotypes are homeostasis/metabolism and nervous system