Eye colour is not solely determined by race. While certain eye colours may be more prevalent in certain ethnic groups due to genetic variations, eye colour is a complex trait influenced by multiple genetic factors. It is primarily determined by the amount and distribution of the pigment called melanin in the iris, which is the coloured part of the eye. Melanin exists in two forms: eumelanin (brown to black pigment) and pheomelanin (yellow to red pigment). The combination and concentration of these pigments determine the colour of an individual’s eyes.
The genetics behind eye colour is not fully understood, but it is believed to involve the interaction of multiple genes. While some eye colours are more commonly associated with certain racial or ethnic groups, it is important to note that eye colour can vary within those groups as well. For example, in populations with a higher prevalence of brown eyes, individuals can still have blue, green, or hazel eyes. Similarly, in populations with a higher prevalence of blue or green eyes, individuals can still have brown or hazel eyes.
Therefore, while there may be some general patterns in eye colour distribution across different racial or ethnic groups, it is not a definitive determinant and individual variation is significant. While it is relatively rare, it is possible for Black individuals to have different eye colours, including blue, green, or hazel. Eye colour is primarily determined by the amount and distribution of melanin in the iris, which is influenced by genetic factors. Although individuals with darker skin tones generally have a higher concentration of melanin in their eyes, there can still be variations in eye colour within any racial or ethnic group.
The occurrence of different eye colours in Black individuals is typically attributed to genetic inheritance from non-African ancestors. Throughout history, there has been migration, mixing of populations, and genetic diversity, leading to a range of eye colours in various populations around the world. This means that individuals of African descent can have diverse eye colours due to their genetic heritage. It’s important to note that while it is possible for Black individuals to have different eye colours, the prevalence is generally lower compared to other populations. The majority of individuals of African descent have brown eyes, which is the most common eye colour worldwide.
Once a person’s eye colour is established in infancy, it is generally considered to be stable throughout their lifetime. However, in some cases, eye colour can appear to change due to various factors such as lighting conditions, clothing colour, makeup, or even emotions. These factors can create the illusion of a temporary change in eye colour, but the underlying genetic makeup of the iris remains the same. There are also certain medical conditions that can cause changes in eye colour. For example, some diseases like Horner’s syndrome or pigmentary glaucoma can lead to a change in the appearance of the iris and affect eye colour. Additionally, certain medications or eye surgeries can also impact eye colour temporarily or permanently. Significant and spontaneous changes in eye colour in adulthood without any underlying medical condition are extremely rare. Eye colour is primarily determined by genetics and is typically established early in life.