The complexity of the color gene is a difficult one to understand. The variation of colors in human eyes is tough to contemplate. The complexity of the eye color gene is so immense that any parent and child within the family can have different eye colors. Not necessarily blue eyes are a recessive trait but they are rather genetic.
Complexity of the Eye Color Gene: Eye color is an inherited physiological trait determined by the the quantity and type of pigments in a person’s iris(iris is located within the eye). The physiological traits associated with eye color cause the variations like blue, green, hazel, brown and argy colors in human eye.
For instance, blue colored eyes can be associated to a certain eye color gene EYCL1 located on chromosome 19(every human has 46 chromosomes). While ECYL2 located on chromosome 15 can be associated to brown eyes. So predicting the eye color of a child is rather impossible, especially after all this complexity involved.
The variation in human eye colors are attributed to the different ratios of eumelanin(a black pigment) produced by melanocytes(cells located in the middle layer of the eye that produce a pigment called melanin) in the iris.
Iris has three crucial elements that determine the eye color of a person:
- melanin content produced by melanocytes in the epethelium(an iris pigment)
- melanin content in stroma(fibrous tissues and cells) of the iris
- the number of cells in the stroma of the iris
The melanin content within the iris stroma is the main attribute that forms the eye color.
Eye color is a trait inherited and is associated with more than one gene.The complexity of the eye color gene renders us helpless in determining the number of genes that actually form the color of the eye. Eye colors can range from a common brown to the most rare green.
