US scientists create ‘Frankenstein’ monkeys

Scientists have found a way to create one monkey from six different embryos – a baby with twelve parents. The medical possibilities are endless, but a moral row has already erupted.

Scientists in the USA have revealed the results of a groundbreaking experiment in which three monkeys were born – each with twelve parents. Showing the healthy six-month-old monkeys to the press for the first time, project leader Shoukhrat Mitalipov said that ‘the possibilities for science are enormous.’

The stem cell research experiment has caused shock and amazement worldwide and involved merging together six fertilised eggs into a single embryo called a chimera, in which cells from all six genetic lines are combined in one body. The technology has been used before on rats and, in 2005, to create a sheep with a partially human brain. The chimera monkeys, named Chemero, Roku and Hex, mark the first time that the experiment has worked with primates. Many scientists believe that it may now be possible with human embryos.

Human chimeras can appear naturally. Occasionally, when two different eggs are fertilised in the womb at the same time, the eggs merge and a single baby is formed. Whilst most human chimeras never become aware of their strange condition, they sometimes have tell-tale quirks such as differently coloured eyes – or in one reported case, ‘chequerboard’ brown and white skin.

In 2003, a 52-year-old American woman was told by doctors that DNA tests showed her to be genetically unrelated to her own sons. Only later was it discovered that the woman was a chimera. Her reproductive system had totally different DNA to other parts of her body; genetically, it was as if she was two different people in one.

Although it is strictly illegal, Mitalipov believes that chimera testing using human embryos is the crucial next step. The team’s ultimate goal will be to find out if carefully selected cells from one embryo can survive when injected into another. If this works, they say, the same could be done with adult humans, helping to fix parts of the body that are damaged by ageing and disease.

Science Friction

Many people who object to this research believe strongly that all people possess an intrinsic identity or soul – even from the moment of conception, when an egg is first fertilised. Two embryos should then have two separate souls. Combining them into a chimera would leave two souls trapped in one body – surely a moral outrage of the the most serious sort.

Not so, reply others. A person’s identity or soul or whatever you believe in has nothing to do with their DNA. A fertilised egg or an embryo is not a person, and a chimera is not two people, or two souls, joined together, but just one person with two sets of DNA.

You Decide

  1. Should scientists be allowed to create chimeras for experiments?
  2. Would a human chimera be one person or two?


  1. What a person is like is partly a result of their genes and partly their environment and experiences as they grow up. Write an essay entitled ‘Nature or Nurture?’ explaining which of these you think is more important, and why.
  2. Watch the video of Kazuo Ishiguro talking about his novel Never Let Me Go and, if you can, read the novel or watch the film for yourself. Write a dramatic monologue or short story from the perspective of one of the ‘clones’ Ishiguro describes.

Some People Say...

“You should never meddle with nature.”

What do you think?

Q & A

Why the great debate?
Chimeras could be used in stem cell therapy, which is thought by many to be medicine’s brightest hope. The range of diseases that could be treated using cells harvested from very young embryos is staggering. But others ask where the right to life begins. Can it be justified to destroy a human embryo, to save a human life? And how much further might scientists be willing to go?
Have other medical developments caused such a fuss?
Yes – many. People once believed that sickness was a punishment from God, so changing attitudes to health and cleanliness was tricky. Human dissection was completely illegal in England until the 16th Century and, when Jean-Baptiste Denys first attempted blood transfusions in the 17th Century, the practice was banned by the French, the British and the Pope.

Word Watch

DNA, or deoxyribonucleic acid, is the genetic code carried in almost every cell in the bodies of humans and animals. Every person’s DNA is individual to them. Only identical twins share the same DNA.
Stem Cell Research
Stem cells taken from embryos are unique because they have the potential to turn into any kind of cell. This means that it could be possible to use stem cells to replace cells in a person’s body which have been damaged by age or disease. However, the cells need to be ‘harvested’ from embryos when they are around five or six-days-old; the embryo itself is then destroyed.
In Greek mythology, the Chimera was a fire-breathing creature, usually depicted as having the head of a lion, the body of a goat and a snake for a tail. In medicine, the term refers to an animal, plant or human which is made up of more than one organism.
The primate family of animals includes monkeys, apes and humans. Primates are our closest animal relatives in the evolutionary tree.
Human reproduction starts with a fertilised egg – a single cell – inside the mother’s womb. This egg, which has its own unique genetic code, then grows into an embryo: a small cluster of cells which will develop into a foetus and, eventually, a human baby. Whether or not an embryo can or should be thought of as a person and/or granted the same rights as a baby already born is a hotly debated and highly emotional issue.

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