n. A difference in colouration in two structures or two parts of the same structure that are normally alike in colour
Photo by Angelos Michalopoulos on Unsplash
Much like a face full of charming freckles, or a strong cleft chin, having two different eye colours is one of those genetic mutations that we can’t but help find appealing. Heterochromia iridis is a condition that effects the iris, resulting in changes to the coloured part of the eye. The affects can change from a subtle difference, to a striking contrast like the perfect pup in the photo below!
There are three main types of heterochromia:
- Complete: Often the most obvious form, as an entire iris of one eye will be a different colour to the other.
- Partial: Where one segment of the iris is a different colour. This can happen in one or both eyes.
- Central: Sometimes harder to spot as the colour change sits close to the edge of the pupil, often with shards of colour beaming outwards.
Photo by Chris Knight on Unsplash
Whilst heterochromia is more common in animals than in humans, the condition affects approximately six in every thousand people; although some of these instances will hardly be noticeable. Largely a genetic trait, heterochromia can also be a result of an illness or caused by an injury to the eye. If you’re a fan of the look, the effect can also be created using coloured contact lenses following a fitting with your optician.