Sa'id bin al-Musayyab (may Allah have mercy on him) said that Sayyiduna Umar bin al-Khattab (may Allah be pleased with him) said: Any man who marries a woman who is afflicted with insanity, leprosy or vitiligo, and he has had intercourse with her, then the dower is due from him, and it will be charged to the woman's guardian.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 14252