Genetics and Eye Color

 

The saying “all babies are born with blue eyes” is a common misconception based on the fact a child’s eye color may appear light at birth, but change overtime. While this may be the case in some situations, eye color is only partially a genetic factor. 

Eye color is determined by melanin production on the outermost layer of the eye. The genetic component of eye color comes from other characteristics that also involve melanin, such as skin color. Darker skin colors tend to have darker-colored eyes, as well as lighter skin colors having lighter colored eyes. Some eye colors overtime evolved as a result of genetic mutation, such as albinism and heterochromia. 

The text describes the literal process of eye color evolution as the following: The cells that determine eye color come from the neural crest cells and migrate into the iris—our eye color cells take about six to nine months to get where they are traveling to.

Sources: 

Article: https://www.parents.com/are-all-babies-born-with-blue-eyes-7550257 

Additional Source: https://medlineplus.gov/genetics/understanding/traits/eyecolor/#:~:text=Both%20ocular%20albinism%20and%20oculocutaneous,eyes%20in%20the%20same%20individual.