a hereditary disease in which numerous benign tumours develop in various parts of the body, especially the skin and the fibrous sheaths of the nerves. It is a form of neurofibromatosis

a disease in which the bones are weakened as a result of excessive secretion of the parathyroid hormone, leading to bowing and fracture of long bones and sometimes deformities of the chest and spine

an inherited disorder characterized by a tendency to bleed, caused by deficiency or abnormality of a plasma coagulation factor (von Willebrand factor)