A Step to Chickenosaurus: Using Indian Hedgehog Gene, Scientists Grow Nonavian Dinosaur Fibula Bone

Molecular development of fibular reduction in birds and its evolution from dinosaurs

Authors:

Botelho et al

Abstract:

Birds have a distally reduced, splinter-like fibula that is shorter than the tibia. In embryonic development, both skeletal elements start out with similar lengths. We examined molecular markers of cartilage differentiation in chicken embryos. We found that the distal end of the fibula expresses Indian hedgehog (IHH), undergoing terminal cartilage differentiation, and almost no Parathyroid-related protein (PTHrP), which is required to develop a proliferative growth plate (epiphysis). Reduction of the distal fibula may be influenced earlier by its close contact with the nearby fibulare, which strongly expresses PTHrP. The epiphysis-like fibulare however then separates from the fibula, which fails to maintain a distal growth plate, and fibular reduction ensues. Experimental downregulation of IHH signaling at a postmorphogenetic stage led to a tibia and fibula of equal length: The fibula is longer than in controls and fused to the fibulare, whereas the tibia is shorter and bent. We propose that the presence of a distal fibular epiphysis may constrain greater growth in the tibia. Accordingly, many Mesozoic birds show a fibula that has lost its distal epiphysis, but remains almost as long as the tibia, suggesting that loss of the fibulare preceded and allowed subsequent evolution of great fibulo–tibial disparity.

pop sci link.

Piecework in a Shell: Transgenic Chickens Approved by FDA, but NOT for Consumption

The US Food and Drug Administration (FDA) has approved a chicken that has been genetically engineered to produce a drug in its eggs.

The drug, Kanuma (sebelipase alfa), is a recombinant human enzyme marketed by Alexion Pharmaceuticals. It replaces a faulty enzyme in people with a rare, inherited condition that prevents the body from breaking down fatty molecules in cells.

Following its approval by the FDA on 8 December, Kanuma joins a small group of ‘farmaceuticals’ on the US market. In 2009, the agencyapproved genetically modified goats that produce an anticoagulant called ATryn (antithrombin) in their milk. And last year, the FDA authorized a drug for treating hereditary angioedema that is produced by transgenic rabbits.

The FDA’s latest decision “shows that the ATryn goats weren’t just a one-off”, says Jay Cormier, a lawyer at Hyman, Phelps and McNamara in Washington DC and a former scientific reviewer for the FDA. “The process can function for more than just one particular unique case.”

The agency moved quickly to consider Kanuma, giving it a priority review, orphan-drug status and a breakthrough-therapy designation. The disease that it is designed to treat, lysosomal acid lipase deficiency, causes fat to accumulate in the liver, spleen and vasculature. A form of the disease that strikes infants is quickly fatal. A second form that affects older patients causes liver enlargement, fibrosis and cirrhosis, as well as cardiovascular disease.

“Before we had this drug, we didn’t have any treatment for the patients that really addressed the underlying biochemical defect in the disorder,” says Barbara Burton, a paediatrician with the Northwestern University Feinberg School of Medicine in Chicago, Illinois. Clinicians could only provide nutrition and supportive care to infants, says Burton, who worked with Alexion to conduct the clinical trials. Older patients are treated with statins—which do not address the fatty build-up in the liver.

link.

Why Did the Chicken Cross the World?

For most of us, the word "chicken" spells a cold, clammy slab of plastic-wrapped white meat plucked out of the refrigerated section of our local supermarket. But in the ancient world, and in many cultures today, chickens had deep religious and social significance.

Speaking from his home in Nashville, Tennessee, Andrew Lawler, author of Why Did the Chicken Cross the World: The Epic Saga of the Bird That Powers Civilization describes how fried chicken has its origins in West Africa, why the Puritans tried to ban the word "cock," and how the backyard chicken movement is bringing roosters to towns and cities all over America.

link.

Chickens Domesticated at the Dawn of the Holocene Quaternary in China

Early Holocene chicken domestication in northern China

Authors:

Xiang et al

Abstract:

Chickens represent by far the most important poultry species, yet the number, locations, and timings of their domestication have remained controversial for more than a century. Here we report ancient mitochondrial DNA sequences from the earliest archaeological chicken bones from China, dating back to ∼10,000 B.P. The results clearly show that all investigated bones, including the oldest from the Nanzhuangtou site, are derived from the genus Gallus, rather than any other related genus, such as Phasianus. Our analyses also suggest that northern China represents one region of the earliest chicken domestication, possibly dating as early as 10,000 y B.P. Similar to the evidence from pig domestication, our results suggest that these early domesticated chickens contributed to the gene pool of modern chicken populations. Moreover, our results support the idea that multiple members of the genus Gallus, specifically Gallus gallus and Gallus sonneratii contributed to the gene pool of the modern domestic chicken. Our results provide further support for the growing evidence of an early mixed agricultural complex in northern China.

Precolumbian South American Chicken Fight

here (dates are fine on the chicken bones).

here. (chicken bones not contaminated by modern chicken dna)

here.  (counter claims have statistical flaws)

The Polynesians (and Their Chickens) did not Cross the Pacific

Did the Polynesians beat Columbus to South America? Not according to the tale of migration uncovered by analysis of ancient DNA from chicken bones recovered in archaeological digs across the Pacific.

The ancient DNA has been used to study the origins and dispersal of ancestral Polynesian chickens, reconstructing the early migrations of people and the animals they carried with them.

The study, led by the University of Adelaide's Australian Centre for Ancient DNA (ACAD) and published today in Proceedings of the National Academy of Sciences USA, reveals that previous claims of contact between early Polynesians and South America were probably based on contaminated results. Instead, the new study has identified and traced a unique genetic marker of the original Polynesian chickens that is only present in the Pacific and Island Southeast Asia.

The research team of national and international collaborators, including Australian National University, University of Sydney, and Durham and Aberdeen Universities in the UK, used female-inherited mitochondrial DNA extracted from chicken bones excavated in archaeological digs from islands including Hawaii, Rapa Nui (Easter Island) and Niue.

"We have identified genetic signatures of the original Polynesian chickens, and used these to track early movements and trading patterns across the Pacific," says lead author Dr Vicki Thomson of ACAD. "We were also able to trace the origins of these lineages back into the Philippines, providing clues about the source of the original Polynesian chicken populations."

Associate Professor Jeremy Austin, ACAD Deputy Director, says: "There are still many theories about where the early human colonists of the remote Pacific came from, which routes they followed and whether they made contact with the South American mainland. Domestic animals, such as chickens, carried on these early voyages have left behind a genetic record that can solve some of these long standing mysteries."

Project leader Professor Alan Cooper, Director of ACAD says: "We were able to re-examine bones used in previous studies that had linked ancient Pacific and South American chickens, suggesting early human contact, and found that some of the results were contaminated with modern chicken DNA, which occurs at trace levels in many laboratory components," says ACAD Director Professor Alan Cooper. "We were able to show that the ancient chicken DNA provided no evidence of any pre-Columbian contact between these areas."

link.

Soooo...where did those chicken bones come from?