The Truth About Eye Color

Originally published at Twixel.net. You can comment here or there.

Eye Color Explained

Everything you know is wrong.

What most people know about the inheritance of eye color is that brown comes from a dominant gene (needing one copy only) and blue from a recessive gene (needing two copies). University of Queensland geneticist Rick Sturm suggests that the genetics are not so clear. “There is no single gene for eye color,” he says, “but the biggest effect is the OCA2 gene.” This gene, which controls the amount of melanin pigment produced, accounts for about 74 percent of the total variation in people’s eye color.

Sturm has recently shown that the OCA2 gene itself is influenced by other genetic components. After gene-typing about 3,000 people, Sturm found that how OCA2 is expressed—and how much pigment a person has—is strongly linked to three single nucleotide polymorphisms (SNPs), or single letter variations, in a DNA sequence near the OCA2 gene. That suggests a more complicated story than the blue-recessive/brown-dominant model of eye color. “For example, among individuals carrying the SNP sequence “TGT” at all three locations on both copies of the gene, 62 percent were blue-eyed,” says Sturm’s colleague David Duffy. By contrast, only 21 percent of individuals carrying only one TGT copy at each location and 7.5 percent of those lacking the TGT entirely had blue eyes.

Depending on the particular combination of SNPs inherited, a person can have a range of OCA2 activity that lands them on the spectrum between blue and brown eyes. What about green eyes? “Green eyes probably represent the interaction of multiple variants within the OCA2 and in other genes, including perhaps the red-hair gene,” Duffy says.

http://discovermagazine.com/2007/mar/eye-color-explained

Bush's Android Army

Got a reply from Senator Cornyn (R-TX) about my letter to him to stop REAL ID.
Expensive, unconstitutional, big government, big brother, unsecure bullshit National ID.

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Dear Ms. Keller:

Thank you for contacting me about national identification cards. I appreciate having the benefit of your comments on this important matter.

As you may know, the REAL ID Act (H.R. 418) was introduced by Congressman James Sensenbrenner on January 6, 2005. It was added to the Emergency Supplemental Appropriations Act for Defense, the Global War on Terror, and Tsunami Relief, 2005 (H.R. 1268), which was introduced by Representative Jerry Lewis on March 11, 2005, and passed the House, as amended, on March 16, 2005. An amended H.R. 1268 passed the Senate on April 21, 2005, by a vote of 99–0, but did not include the REAL ID Act provisions.

A conference report resolving differences between the two versions of the bill (H.Rept. 109-72) passed the House on May 5, 2005, and the Senate on May 10, 2005, before being enacted into law on May 11, 2005. The version of the REAL ID Act (P.L. 109-13, Division B) ultimately enacted includes most of the provisions of the REAL ID Act that initially passed the House, though some changes were made to certain REAL ID Act provisions. I supported the REAL ID Act as I believe it to be an important component of national security.

I appreciate having the opportunity to represent Texans in the United States Senate. Thank you for taking the time to contact me.


Sincerely,

JOHN CORNYN
United States Senator


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He's a remote control robot for Bush. Does absolutely everything he's told. I sometimes wonder why I bother.

Thanks for the detailed explanation of WHY you support this piece of crap, jackass.