Why Can’t My Eyes Be Purple? Why Eyes Only Come In Certain Colors
The color of our eyes has always been one of the most fascinating individual traits of the human body. How and why they develop how they do is, to some extent, still a mystery, and while we know how iris colors like blue and brown are formed the truth is that we know relatively little about the complex processes beyond that. One question which crops up a lot is why we are generally limited to the select few iris colors we have – excluding the influence of medical conditions our eyes tend to be some form of brown, blue or green, so why can they not be bright purple?
Genetics Determine Eye Color
As with most things in our body, the answer lies in genetics. Our eye color is determined by a selection of genes at various points in our body passed onto us from our parents. These genes code for – you guessed it – brown, blue and green by containing data on how much melanin we produce (the coloring pigment in our eyes and skin).
The color that we end up with is a result of the proportions of these genes; much like using paints, no amount of mixing them will produce purple, turquoise or any other shade which is not a combination of these three. Genes for other colors do not exist, and so other colors are not possible.
Can we modify our eye color?
There are a small number of disorders which result in a defect of melanin production and thus a different eye color, such as albinism which causes pink eyes.
Aside from this, there are precious few options if you’re looking for a more striking color. The most obvious choice is to wear colored contact lenses – certainly the safest option so long as lenses are prescription (regardless of whether they have any power) and are bought from an approved optician. A company known as Stroma Medical have also recently announced that they are working on a form of laser which can permanently lighten dark eyes. The process seems to work through scattering melanin pigments and thus resulting in a more diluted color – meaning that darkening light eyes would not be possible.
Of course, assuming that this passes safety approval tests (which may be a difficult enough challenge as it is) it won’t be able to completely change our eye color even if we are trying to move from a dark brown to a light purple, as this would require some form of eye coloring technology.
We’ve also recently seen the introduction of eye tattoos which tend to be performed on the whites of our eyes. Whether this coloring would be possible on the iris is yet to be tested, though there is still healthy skepticism over the risks of eye tattooing as a whole, so it would be best avoided for now.
Rob writes for Direct Sight – a leading supplier of reading glasses online.