Exact cause of the disorder is still unknown. A combination of factors, which include genetic predisposition, disturbance in immune system, environmental triggers and other known and unknown exogenous precipitating factors, are thought to be responsible for the development of Vitiligo.
Antibodies in the form of white blood cells (lymphocytes) are formed in the body, which destroy melanocytes (pigment cells). Why this happens is not exactly known. Vitiligo is also associated with other autoimmune disorders such as Psoriasis, Thyroid disease, Alopecia Areata, etc.
Some observers feel that there is an unknown chemical substance released at nerve-endings, which destroy pigment cells. None of these causes have been proved conclusively yet.