Blue eyes under a gene switch

2008/03/01 Elhuyar Zientzia Iturria: Elhuyar aldizkaria

• Genetika
• Anatomia/Fisiologia

Blue eyes owe their color to a gene that breaks the ability of the eyes to produce brown color, according to a study by the University of Copenhagen.

The OCA2 gene is one of the genes that color human eyes, produce melanin and give brown color to the eyes. When it has certain mutations it gives hazelnut or green color. Knowing this, scientists sought in that gene the mutation that produced the blue color, but neither found it looking much.

The Copenhagen team has found why: the cause of blue eyes is not the OCA2 gene, but the HERC2 gene next to it, when it suffers a certain mutation. In this situation, it acts as a switch of the OCA2 gene, that is, it interrupts the production of the OCA2 gene and that is when the blue eye is formed.