A retrovirus makes chicken eggshells blue

When you purchase chicken eggs at the market, they usually have white or brown shells. But some breeds of chicken produce blue or green eggs. The blue color is caused by insertion of a retrovirus into the chicken genome, which activates a gene involved in the production of blue eggs.

The Araucana, a chicken breed from Chile, and Dongxiang and Lushi chickens in China lay blue eggs. Blue eggshell color is controlled by an autosomal dominant gene: eggs produced by homozygote chickens are darker blue than those from heterozygotes. The gene causing blue eggshell color is called oocyan (O) and was previously mapped to the short arm of chromosome 1.

To further refine the location of the O gene, genetic crosses were performed using molecularColorado, Washington OK recreational marijuana use

Laura S. Bly | USATODAY

Colorado and Washington became the first states to legalize the recreational use of marijuana Tuesday, prompting speculation about Amsterdam-style "drug tourism" and a new round of jokes about Colorado's official song, Rocky Mountain High.

But because the ballot measures directly contradict federal law, observers say implementation is uncertain.

"The voters have spoken and we have to respect their will," said Colorado Gov. John Hickenlooper, who opposed his state's constitutional amendment. "This will be a complicated process, but we intend to follow through. That said, federal law still says marijuana is an illegal drug, so don't break out the Cheetos or Goldfish too quickly."

The Drug Policy Alliance, a national advocacy group that backed the initiatives, told Reuters the outcome in Washington and