Green eyes probably result from the interaction of multiple variants within the OCA2 and other genes. They were present in south Siberia during the Bronze Age.
They are most common in Northern and Central Europe. They can also be found in Southern Europe, Middle East, and parts of South and Central Asia (Afghanistan, India, and Pakistan). In Iceland, men and women men have either blue or green eye color. A study of Icelandic and Dutch adults found green eyes to be much more prevalent in women than in men. Among European Americans, green eyes are most common among those of recent Celtic and Germanic ancestry.