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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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There is defect in production of melanin in all except-
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The correct answer is  In melasma is a accuired hyperpigmentary disorder affecting predominantly over face. etiology is ultra violet rays. It is also triggered by pregnancy and oral contraceptive pills. All the other given conditions are associated with defects in melanin pproduction IADVL textbook of dermatology, pigmentary disorders,page745