Researchers have reportedly edited the genomes of human embryos using a technique called CRISPR. While scientists in China have used the same technology to genetically modify human embryos, this is believed to be the first attempt in the U.S.
The feat, led by Shoukhrat Mitalipov from Oregon Health & Science University, is viewed with trepidation by medical ethicists and some scientists, including those who developed the CRISPR technology. The fear is that it can lead to manipulating the human genome at will—not only to correct genetic defects, but to enhance certain human characteristics, such as athleticism and intelligence, and remove those viewed as undesirable.
MORE: How Scientists Think CRISPR Will Change Medicine
CRISPR, which was only discovered five years ago, gives scientists unprecedented power to precisely and accurately make changes to the genome. In 2015, a group of scientists called for a worldwide moratorium on using CRISPR to edit the genomes of human embryos, eggs and sperm, which can pass on the genetic changes to future generations, until more information about the reliability and safety of the relatively new technology is collected. The National Institutes of Health also does not fund studies involving CRISPR in human embryos. However, earlier in 2017, the U.S. National Academy of Sciences reviewed the potential uses of CRISPR and opened the door for research studies in embryos if the work would address serious inherited diseases.
MORE: How the Science of CRISPR Can Change Your Genes
At issue is the fact that genetic editing in embryos involves so-called germline cells, which give rise to all of the cells in the resulting embryo. These changes would also survive into that individual’s sperm or egg cells and would be passed on to future generations as well. That could result not just in designer babies, but in significant shifts in the gene pool that could have unpredictable consequences, ethicists say.
That’s not the case with using CRISPR to correct somatic cells, which don’t give rise to egg and sperm. U.S. regulators approved the first such trial to test CRISPR in correcting genetic defects last year.
Mitalipov’s work is expected to be published in a major scientific journal.
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