Chinese scientists recently developed monkey-pig hybrids called chimera as a part of their research into the growth of human organs for transplantation in animals. Although they died within a week of being born, the piglets carried DNA from macaque monkeys in their heart, liver, spleen, lung and skin. The monkey-pigs were bred from more than 4,000 embryos that were implanted into a sow using IVF. Chimera is a single organism which carries cells with distinct genotypes. Animal chimeras are produced by merging multiple fertilised eggs. In this case, they contained DNA from individuals, a pig and a monkey. Human Chimeras also exist but are quite rare. They contain the cells of two or more individuals. Their bodies contain two different sets of DNA. Around 100 cases of chimerism have been recorded in the modern medical literature. First Monkey-Pig Chimeras Created by Chinese Scientists, Die Within a Week (See Picture)
What is Chimera?
While chimera is today used to refer to a hybrid variety of animals or to about an impossible thing, the word has a reference in Greek mythology. According to which, chimera is a fantastical beast made from different animals. It is named after a fire-breathing monster which had the head of a lion, the body of a goat and serpent's tail. Chimera is also the Greek term for a female goat.
How Were Monkey-Pigs Created?
To create pig-primate chimeras, Tang Hai, a researcher at the State Key Laboratory of Stem Cell and Reproductive Biology in Beijing and his co-authors first grew cells from cynomolgus monkeys (Macaca fascicularis) in lab dishes. The altered the cell's DNA by inserting instructions to build a fluorescent protein that made the cells bright green in colour. These luminescent cells gave rise to radiant embryonic stem cells which were then injected into pig embryos. These glowing spots helped researchers to track the monkey cells as the embryos grew into piglets in due time.
In total, 4,000 embryos received an injection of monkey cells. The pigs bore 10 piglets but only two of them grew into both pig and monkey cells. The team found monkey cells scattered throughout multiple organs, including the heart, liver, spleen, lungs and skin. It was that in each organ, between one in 1,000 and one in 10,000 cells turned out to be monkey cells which were they were 99 percent pigs.