<unk>  can cause many symptoms, such as: * Poor vision (not always present) * More sensitivity to light * Fast, uncontrolled, shaking "to and fro" eye movements (nystagmus) * Eyes don't line up (strabismus)
Aniridia
Xanthochromia
Microphthalmia
Heterochromia iridum
Macrodontia 
Spotted lunulae
Onychoschizia
Dyschromia