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SAVINGRACE
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"Biologists in China have carried out the first experiment to alter the DNA of human embryos, igniting an outcry from scientists who warn against altering the human genome in a way that could last for generations.
The experiment used a controversial technique called CRISPR/Cas9, and represents a biological version of the “find and replace” function on a word processing program."
Scientists introduced enzymes that first bind to a mutated gene, such as one associated with disease, and then replace or repair it.
The study’s lead author Junjiu Huang, of Sun Yat-sen University in Guangzhou, and his team experimented on 86 one-cell human embryos, all from fertility clinics, that because of chromosomal defects were unable to develop into a baby.
Their target was a gene called HBB, which can cause the blood disease beta thalassemia.
About a dozen embryos did not even survive the genome-editing, the scientists reported, and of the surviving embryos, many showed “off-target” effects meaning genes other than HBB were altered.
Other embryos suffered “untoward mutations” and only a handful of embryos contained the healthy DNA meant to repair the defective HBB genes.
Mr Huang told Nature News that if this was done on normal embryos “you need to be close to 100 per cent” on target in terms of fixing only the target gene."
abc.net.au/news/2015-04-24/human-embryos-editing-experiment-ignites-ethical-furore/6418818
The experiment used a controversial technique called CRISPR/Cas9, and represents a biological version of the “find and replace” function on a word processing program."
Scientists introduced enzymes that first bind to a mutated gene, such as one associated with disease, and then replace or repair it.
The study’s lead author Junjiu Huang, of Sun Yat-sen University in Guangzhou, and his team experimented on 86 one-cell human embryos, all from fertility clinics, that because of chromosomal defects were unable to develop into a baby.
Their target was a gene called HBB, which can cause the blood disease beta thalassemia.
About a dozen embryos did not even survive the genome-editing, the scientists reported, and of the surviving embryos, many showed “off-target” effects meaning genes other than HBB were altered.
Other embryos suffered “untoward mutations” and only a handful of embryos contained the healthy DNA meant to repair the defective HBB genes.
Mr Huang told Nature News that if this was done on normal embryos “you need to be close to 100 per cent” on target in terms of fixing only the target gene."
abc.net.au/news/2015-04-24/human-embryos-editing-experiment-ignites-ethical-furore/6418818