Exactly how is a person's eye color determined? It depends on the amount, type and distribution of melanin, or pigment, in the iris of the eye, a genetics expert reveals — and more.

Two genes, OCA2 and HERC2, work together to determine melanin content and, thus, eye color. “The OCA2 gene sits next to HERC2, and HERC2 has elements that control the regulation of the OCA2 gene ...

Previous studies had revealed some genes behind melanocyte maturation and melanin production, but only enough to explain between 23% and 35% of the variation in human skin color, Wysocka and her ...

Other genes that play a role in eye color. OCA2 isn’t the only gene that has a say in what color eyes you’re born with. There’s HERC2, a gene that controls how the OCA2 gene works, ...

Eye color genes are critical for retinal health. ScienceDaily. Retrieved June 2, 2025 from www.sciencedaily.com / releases / 2023 / 03 / 230323154215.htm.

Eye color is determined by genetics, of course, but the genes associated with eye color are directly connected to the production, use and storage of a pigment called melanin.

But, unlike simple inheritance patterns, eye color isn’t determined by a single gene. Multiple genetic markers contribute to the final shade, making it not always easy to predict the final outcome.

Abnormal eye color arises due to mutations in genes that regulate pigment formation and a specific metabolic pathway. view more . Credit: Hebbar et al., Plos Genetics, 2023 / MPI-CBG.

Discover how your eye color genetically determines pain sensitivity, why dark eyes handle pain better, and what this means for you.

There are some genes, however, that impact hair color that may not impact eye color and vice versa, she said. Never Miss a Story Sign up to get the best stories straight to your inbox.

The eye-color gene. Just as the MC1R gene determines your hair color, a single gene, OCA2, is 75% responsible for your eye color, Dr. Kaplan says.