When I was younger I always wondered why some people have brown eyes and others have blue eyes. (I know that there are other eye colors but I'm going to stick to the most common two) So I did some research and instead I saw that some people have two different eye colors and I really wanted to see how could happen.Having different colored eyes is very rare in humans. It actually usually only occurs in animals like huskies, cats, or horses because of inbreeding. But it did happen to people like David Bowie and Christopher Walken.
Okay, so heterochromia tends to happen when something has gone wrong in making the eye color or if the body shuts off a gene in only some cells of the body. Heterichromia can be the result of too much pigment in the iris or not enough in one of the eyes. This can happen either because of genetics or some type of injury.
When there is too much pigment in the iris it results in a brown eye, and when there is not enough or a little amount, it results in a blue eye. The pigment is made in cells called melanocytes. If anything happens that could affect the health of one of these cells, it won't have pigments which will make the eye blue.
Another way you could end up having different eye colors is having two different eye color genes. How is this possible? Well, let me explain...
According to thetech.org, melanocytes are made in the growing fetus. Once they are made, they have to migrate to the right spots (such as skin and eyes). If something affects their growth or their ability to travel, then they die off. To end up making pigments in the right place, melanocytes need a variety of signals from other cells. This network of cells is pretty easily disrupted. For example, if a fetus sufferes some type of head injury, it could kill some important cells that help the melanocyte develop.
The third way you could end up with different eye colors is being diagnosed with Waardenburg syndrome. That's when mutations in certain genes that cause some melanocytes to get lost on their way to where they are supposed to go. Some people with this syndrome can end up with an eye that has no pigments (a blue eye) or a patch of skin that is not the same color as your regular skin tone.
I have blue eyes. This was very interesting good to know
ReplyDeleteIn the picture, the man's eyes are dialated at different widths. Is that an actually effect? or is it just used to catch the attention of the viewer to notice the different eye colors?
ReplyDeleteIn your blog you said that brown eyes are caused by there being "too much" pigments and blue eyes "not enough", so are you saying that people with brown or blue eyes have an incorrect amount of eye pigments? If so, which eye color has the “correct” amount of eye pigments?
ReplyDeletethis is really interesting! do you think there would be a possibility for such mistakes in development to be corrected?
ReplyDeleteIn the pictures the pupils appear to look much different so does this cause one eye to be nonfunctional or at least not as strong as the other
ReplyDelete@nsrouji it probably has the possibility to be corrected there was a post about that in November I believe...
ReplyDelete