A difference in color between the iris of one eye and the iris of the other eye. A person with one brown eye and one blue eye has heterochromia iridis. It is a rare inherited genetic disorder in which the body cannot process the amino acids phenylalanine and tyrosine, which occur in protein.
- Dark spots in the sclera (white) of your eyes.
- Thickened and darkened cartilage in your ears.
- Blue speckled discoloration of your skin, particularly around sweat glands.
- Dark-colored sweat or sweat stains.
- Black earwax.
- Kidney stones and prostate stones.
Heterochromia iridis is caused by a mutation on your homogentisate 1,2-dioxygenase (hgd) gene. It's an autosomally recessive condition. This means that both of your parents must have the gene in order to pass the condition on to you. Alkaptonuria is a rare disease.