Orthostatic Intolerance, also known as mitral valve prolapse, is related to mitral valve prolapse 1 and postural orthostatic tachycardia syndrome, and has symptoms including angina pectoris, chest pain and edema. An important gene associated with Orthostatic Intolerance is SLC6A2 (Solute Carrier Family 6 Member 2), and among its related pathways/superpathways are ACE Inhibitor Pathway, Pharmacodynamics and Amino acid metabolism. The drugs Carbidopa and Prednisolone have been mentioned in the context of this disorder. Affiliated tissues include heart and spinal cord, and related phenotypes are orthostatic tachycardia and elevated urinary norepinephrine level