Sa'id (may Allah have mercy on him) said that Sayyiduna Umar (may Allah be pleased with him) said: Whoever marries a woman who is insane, has leprosy, has vitiligo or has qarn (an obstruction of bone or flesh in the private part), then if he has had intercourse with her, the dowry must be paid, and it is upon her guardian.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النكاح / 14224