Genetic and physical factors determining iris color thumb|A light brown iris with prominent limbal ring. Light brown irises contain pheomelanin. Iris color is a highly complex phenomenon consisting of the combined effects of texture, pigmentation, fibrous tissue, and blood vessels within the iris stroma, which together make up an individual's epigenetic constitution in this context. An organism's "eye color" is actually the color of one's iris, the cornea being transparent and the white sclera entirely outside the area of interest.
Genetic and physical factors determining iris color thumb|A light brown iris with prominent limbal ring. Light brown irises contain pheomelanin. Iris color is a highly complex phenomenon consisting of the combined effects of texture, pigmentation, fibrous tissue, and blood vessels within the iris stroma, which together make up an individual's epigenetic constitution in this context. An organism's "eye color" is actually the color of ,one's iris, the cornea being transparent and the white sclera entirely outside the area of interest.