https://fcserver.nvnet.org/~ryans/FOV1-0004A022/FOV1-00050562/GenBluEyeColr-Eiberg.pdf ''Blue eye color in humans may be caused by a perfectly associated founder mutation in a regulatory element located within the HERC2 gene inhibiting OCA2 expression'' - Eiberg H, Troelsen J, Nielsen M, Mikkelsen A, Mengel-From J, Kjaer KW, Hansen L., Hum Genet. 2008;123:177-187. PubMed ID:18172690
Conclusion
In conclusion, we have identified a conserved regulatory element within intron 86 of the HERC2 gene that is perfectly associated with the brown/blue eye color in studied individuals from Denmark, Turkey and Jordan. This element had an inhibitory efect on the OCA2 promoter activity in cell cultures, and the blue and the brown alleles were shown to bind non-identical subsets of nuclear extracts. In total, all these data strongly support a model where the blue eye color in humans is caused by homozygosity of the rs12913832*G allele.
Dr Eiberg: In human beings, brown eyes are the default and blue occurs only when that default is turned off. Eiberg says when the first blue-eyed mutation occurred, the person who carried it would have had brown eyes. But as time proceeded, a man and a woman who each carried that one blue-eyed gene mutation mated and produced the world's first blue-eyed baby. Eiberg suspects that would have been a huge surprise to them. "If the child was the only one to have blue eye color and everyone else has brown, it could have been very interesting," he told...
***Inheritance of blue-eye color is determined by THE PRINCIPLE OF RECESSIVE. It is necessary that both parents - FATHER AND MOTHER - carry the appropriate mutation genes! It does not apply the cumulative principle or the principle of addition.
The researchers' hypothesis about the place of origin of mutations related to the Balkans, the Middle East and north-west coast of the Black Sea - in the Neolithic periods about 6.000 - 10.000 years ago.
Blue eyes are very common in countries near the mutation epicenter, which the researchers have pinpointed to be somewhere in the Balkans or near the Black Sea.
***The high frequency of blue-eyed individuals in the Scandinavia and Baltic areas indicates a positive selection for this phenotype (Cavalli-Sforza et al. 1994; Myant et al. 1997). Several theories has been suggested to explain the evolutionary selection for pigmentation traits which include UV expositor causing skin cancer, vitamin D deficiency and also sexual selection has been mentioned. Natural selection as suggested here makes it difficult to calculate the age of the mutation.
***Racist theories about the origin of the color of eyes, hair and skin often limited/prevents people from logically consistent and linked to the fact...