Heterochromia is the best "disease" you can get

Heterochromia of the eye (heterochromia iridis or heterochromia iridum; the common incorrect form "heterochromia iridium" is not correct Latin) is of two kinds. In complete heterochromia, one iris is a different color from the other. In partial heterochromia or sectoral heterochromia, part of one iris is a different color from its remainder.