Final answer:
Vitiligo is an acquired condition characterized by the loss of melanin pigment, resulting in white patchy areas on various parts of the body. It is caused by a malfunction of melanocytes, possibly due to an autoimmune reaction, and does not directly affect lifespan but requires management to protect the skin and address psychological impacts.
Step-by-step explanation:
The acquired condition characterized by the absence of melanin pigment and light (white) patchy areas on various parts of the body such as the face, hands, feet, neck, orifices, and folds is known as vitiligo. This occurs when melanocytes, the cells responsible for producing melanin, lose their ability to function, possibly due to an autoimmune reaction, leading to depigmentation and the formation of white patches on the skin. Vitiligo is more noticeable on darker skin and does not directly affect an individual's lifespan, but it can cause psychological and emotional stress. Treatment for vitiligo is aimed at restoring the skin's color and protecting it from the sun's UV rays. This disorder is different from albinism, which is a genetic condition where there is a complete or partial lack of melanin production throughout the body.