Monday, March 03, 2008

Mendel's Garden #24 - March 2008

March has roared in like a lion; the freezing rain here may not be great for venturing outdoors, but it's perfect for a virtual walk through Mendel's Garden, your monthly carnival of genetics. Welcome to the 24th edition.

Greg Laden starts us off with some true garden fodder: the potato. There, he tries to get to the bottom of the potato origins debate: Did the European potato come from the Andes or from Chile? The answer is important. As Greg informs us:
"[G]etting the history right is very relevant to developing potato varieties that are both, well, good at being potatoes, and resistant to blight."
As if knowing where your fries are from wasn't enough, Greg also delves into the origins of your 20-piece bucket. In his piece "The Origin of the Chicken", he explains new genetic evidence that the domestic chicken is actually a hybrid of (at least) two South-east Asian jungle fowl.

Now that we know where the chicken comes from, GrrlScientist lets us know how old they are in another bird-related post. In her piece "Rocks vs Clocks: When Did Modern Birds Really Appear? ", she discusses a recent paper challenging the notion that modern birds first appeared 60-65 MYA, as the fossils previously suggested. When molecular clock corrections are applied to the phylogenetic tree to date the branching of the bird lineage, the last common ancestor with dinosaurs appears to be much older, around 100MYA.

If you're a paleontologist, and you now find yourself between a rock and a hard place, but yet still cheering the discovery, perhaps you should look out for signs of bipolar disorders. Grrlscientist comes to the rescue, describing a recent controversial report of a blood test for bipolar disorder. She Laments that the discovery:

"presents great opportunities for research combined with terrible opportunities for abuse."

Finally we wrap this up with a homegrown post on another neurological disorder, autism, whose genetic basis is finally getting unraveled. Recent findings point to a location on chromosome 16 and copy number variation as the culprits in a subset of afflicted individuals. You can find the list of genes at that locus, and bet on your favorite candidates.

That concludes this edition. Submit your blog article to the next edition of
mendel's garden using our carnival submission form. Past posts and future hosts can be found on our blog carnival index page.