Trivia de la nuit: all blue-eyed people are descended from a common ancestor, posited to have lived in the Black Sea area between 6500-10,000 years ago, who carried a unique mutation. This mutation, which is found in an intron in the HERC2 gene, reduces the activity of a neighboring gene, OCA2. The OCA2 gene codes for the "P protein", which is involved in the production of melanin. The HERC2 gene affects the OCA2 and reduces the production of melanin in the iris, diluting brown eyes to blue.
If the gene had been completely shut down, we would have albinism instead. As virtually all blue-eyed people tested have been shown to have the same gene mutation that codes for iris color in the same haplotype, or set of DNA variations, we can conclude that blue-eyed people all share a common ancestor who lived within this time frame. If the trait had evolved in different populations, the mutation would not be found only in the same haplotype with the same combination of SNPs ('snips' are single nucleotide polymorphisms--single nucleotide substitutions of one base for another).
As I also have blue eyes, I'm a bit curious as to why long-lost cousin Craig did not show up at the Thanksgiving table. I think it was his turn to bring the creamed onions too. Figures.
In honor of the franchise's fiftieth anniversary, I'm off to hunt for Ian Fleming on Kindle.
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