<prompt> Answer this question truthfullyWhat is the pathophysiology of Behçets disease?  <response>: <reason> The development of Behçet disease is the result of multiple genetic mutations. Genes involved in the pathogenesis of Behçet disease include human leukocyte antigens, particularly HLA -B51. Familial cases of Behçet disease have higher rates of HLA -B51 in compare to sporadic cases. Genetic anticipation: earlier age of onset of disease in children of patients with Behçet disease. Some studies shows that major histocompatibility complex class I chain related gene A MICA A6 allele is related to Behçet disease. Non- HLA genes also have roles in Behçet diesease. They include: Intercellular adhesion molecule ICAM-1 gene Endothelial nitric oxide synthase gene Tumor necrosis factor TNF genes Vascular endothelial growth factor VEGF gene Manganese superoxide dismutase gene Cytochrome P450 gene Interleukin IL-10 gene IL-23 receptor gene Missense mutations of the familial Mediterranean fever MEFV gene that encodes protein pyrin on the surface of neutrophils 