Tuesday, 13 May 2008

Genetically Modified Human Embryo Stirs Controversy

Scientists create first GM human embryo 
Tuesday, 13 May 2008 

Researchers at Cornell University in New York have made a breakthrough in genetics by creating the first genetically modified (GM) human embryo. The GM embryo was produced to study how early cells in the embryo develop, but the scientists destroyed it just after five days. Led by Nikica Zaninovic, researchers at Cornell University used a virus to add a gene, a green fluorescent protein, to an embryo left over from assisted reproduction. It is believed to be the first documented genetic modification of a human embryo. 

Zaninovic's achievement was announced at the American Society for Reproductive Medicine annual meeting in 2007, but was only publicized recently when the United Kingdom's reproductive technology regulators reviewed the research. One of the authors of the study said to AP that the work was focused on stem cells. He noted that the researchers used an abnormal embryo that could never have developed into a baby anyway. 

"None of us wants to make designer babies," said Dr. Zev Rosenwaks, director of the Center for Reproductive Medicine and Infertility at New York-Presbyterian/Weill Cornell Medical Center. Dr. Rosenwaks said the research had been approved by a review board at his medical center and been privately financed, so it did not violate federal restrictions on research involving human embryos. 

 Doctors already put foreign genes into people as part of gene therapy to treat diseases. But those genetic changes generally cannot be passed on to future generations because they are made to only certain types of cells in the body, like blood cells or muscle cells. Genetic changes made to an embryo would theoretically be heritable if the embryo became a baby. So far, this has been a no-go area for scientists and medical professionals. 

 The breakthrough has brought with it major concerns. The British regulator, the Human Fertilisation and Embryology Authority (HFEA), has even cautioned that such controversial experiments may lead to "large ethical and public interest issues". However, the HFEA has said that it is preparing for scientists to apply for licences to create GM embryos. 

A paper, published by the authority, states: “The bill has taken away all inhibitions on genetically altering human embryos for research. The Science and Clinical Advances Group [of the HFEA] thought there were large ethical and public interest issues and that these should be referred for debate.” 

 The House of Commons in Britain is about to consider legislation permitting this and other controversial reproductive technologies, such as the creation of chimeras – human-animal hybrid embryos. The first voting on this Bill took place yesterday in the British Parliament. There the MPs voted to allow, with a great majority, the plan to update the human embryology laws to continue to their next Parliamentary stage. The research raises a number of difficult ethical questions. 

Though adding a fluorescent protein was merely a proof-of-principle step, modified embryos could be used to research human diseases. Scientists say embryos wouldn't be allowed to develop for more than a few weeks, much less implanted in a woman and brought to term. If the embryos were allowed to develop, genetic modifications – which would be permanent and passed to future generations – might prevent disease. 

Modifications might also be used for other reasons – physical appearance, intellectual prowess and personality changes – though the necessary science remains hypothetical at this point. Developing such techniques would necessarily involve at this stage trial-and-error and risk-taking with human life.

Let's have that debate:
What do you think CellNEWS readers? 

  • Should genetically modified human embryos be used in research, or reproduction? Both? Neither? 
  • What would be the advantages or disadvantages? 
  • Would it OK to produce ‘designer babies’ in the future, when the technique is perfected? 

Reference: 
N. Zaninovic, J. Hao, J. Pareja, D. James, S. Rafii, Z. Rosenwaks. 
ASRM 2007 Annual Meeting, Poster session. 

Other Online Resources: 
HFEA 
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ZenMaster

For more on stem cells and cloning, go to CellNEWS 
at http://cellnews-blog.blogspot.com/

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