Vitiligo is depigmentation of the skin. It causes the skin to lose color, and patches of lighter skin appear. This happens when the melanocytes (skin pigmentation cells) die or cannot function. It is not contagious or dangerous.
The exact cause is unknown but may be triggered by genetics, a virus or an autoimmune response. An autoimmune response causes the immune system to attack some part of the body by mistake. Other possible, but unproven factors include sunburn, emotional distress and self-destruction of melanocytes.
Vitiligo usually affects people in their twenties, but the condition can occur at any age. The disorder affects all races and both sexes equally. However, it is more noticeable in people with darker skin.
People with certain autoimmune diseases (such as hyperthyroidism) or parents who have vitiligo are more likely to get vitiligo.