People with blue eyes share a common ancestor, as shown by a study from the University of Copenhagen. A team of scientists from the Department of Cellular and Molecular Medicine determined that a genetic mutation occurred between 6000 to 10,000 years ago in a human who lived in the northwest region of the Black Sea. Through a genetic mutation in the OCA2 gene, responsible for melanin production, the pigment that influences the color of our hair, eyes, and skin, melanin production was reduced.

On the 15th chromosome, there are two main genes that affect eye color – OCA2 and HERC2. Eye color depends on the amount and distribution of melanin in the iris of the eye. In cases where the OCA2 gene is destroyed, individuals lack melanin in their hair, eyes, and skin. This condition is known as albinism.

Scientists at the University of Copenhagen identified, based on a sample of 800 participants, that all but one individual share the same genetic mutation originating from a common ancestor, a trait shared by many well-known blue-eyed figures such as Paul Newman, Frank Sinatra, Taylor Swift, Brad Pitt, and Alexis Bledel.