Irisfarge

Irisfarge is a term that refers to the color of a person's iris, the colored part of the eye. This coloration is determined by the amount and type of melanin present in the iris stroma. Melanin is the same pigment that gives color to skin and hair. The iris stroma is the front layer of the iris, and it contains specialized cells called melanocytes.

The most common iris colors are brown, blue, and green. Brown eyes are the most prevalent worldwide and occur when there is a high concentration of melanin in the iris. Blue eyes, on the other hand, have very little melanin. The blue appearance is due to the scattering of light by the stroma, a phenomenon known as Rayleigh scattering, similar to why the sky appears blue. Green eyes result from a moderate amount of melanin combined with light scattering.

Other iris colors, such as hazel, amber, and gray, are variations of these basic colors. Hazel eyes often appear to change color depending on the lighting conditions due to a mix of brown and green pigments and light scattering. Amber eyes have a more uniform golden or reddish-brown hue. Gray eyes are similar to blue eyes in that they have low melanin content but may have a different collagen structure in the stroma, leading to a grayish appearance.

Genetics plays a significant role in determining iris color. Multiple genes influence melanin production and distribution, with contributions from both parents. While it was once thought to be a simple Mendelian trait, it is now understood to be a complex inheritance pattern.