What role the OCA2 gene plays in blue eye color.
What was the original eye color of man?

1. Some 6,000 to 10,000 years ago, a genetic mutation affecting one gene turned off the ability to produce enough melanin to color eyes brown causing blue eyes. This mutation arose in the OCA2 gene, the main gene responsible for determining eye color

2. All humans had brown eyes

Explanation:

I had this in biology and got it correct :)