The eyes have it

Via the BBC:

Scientists have made a breakthrough in their understanding of the genetics behind human eye colour.

They found that just a few “letters” out of the six billion that make up the genetic code are responsible for most of the variation in human eye colour.

The research, by a team of scientists from Queensland, Australia, will appear in a forthcoming issue of the American Journal of Human Genetics.

The findings are based on a genetic study of nearly 4,000 individuals.

Differences in eye colour are largely down to “single nucleotide polymorphisms” (SNPs – pronounced “snips”); variations in the sequence of letters that make up a single strand of human DNA.

SNPs represent a change of just one letter in the genetic sequence. These changes, or mutations, in our DNA can have important consequences for how the gene gets physically expressed.

All the SNPs are located near a gene called OCA2. This gene produces a protein that helps give hair, skin and eyes their colour. And mutations in OCA2 cause the most common type of albinism.

Brown and blue

The study, which focused on twins, their siblings and parents, shows – conclusively – that there is no “gene” for eye colour.

Does this mean ‘so long’ to the long-held belief that recessive genes were responsible for the color of your eyes?

Hat tip to Kim Priestap, who posted a picture of one of her eyes as the opener to her blog post about this. Here are some eye pix of my mom, sis, and me:


ST’s eldest sis


ST’s middle sis


ST


ST’s mom (I had to blow the pic up a bit, but hopefully the hazel-green of her eyes shines through – it does to me :) )

And these scientists are saying that there is no gene for eye color? C’mon!

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