Not long ago, the ability to alter DNA of any organisms, including human embryos, was an idea thought up by science fiction authors and movie directors. A new technique, called CRISPR, however is proving not only that it’s possible, but that it can be done very easily and at very little cost when compared to prior gene editing attempts. And as a result- it is being adopted in labs everywhere.
CRISPR stands for clustered regularly interspaced short palindromic repeats. The method, which is being touted as a way to completely eliminate genetic diseases- employs a nuclease enzyme called Cas9 that uses an introduced guide RNA molecule to find a unique DNA target sequence in living cells. The enzyme then cuts the DNA, which can be repaired to disrupt an unwanted gene or edited to change or repair a gene. The total cost to do this in a laboratory has been as little as $30. CRSIPRs have made it much easier and cheaper to make gene knockouts in mice and other experimental organisms.
The speed of which CRISPR is sweeping the world is causing a great deal of excitement in the research arena, but also concerns among the risk of unintended side effects such as off-target cutting, the unknown impact of altered organisms on ecosystems, and the ethics of altering human embryos. While researchers were actively debating the tenets, news broke in April of 2015 that embryos in China had been modified. While the embryos did not result in a birth, the seal was officially broken, and it was made clear that CRISPR’s impact on the human population will be tremendous, for better or for worse.
The pharmaceutical industry has begun to look into CRISPR-based gene therapy, with first trials likely beginning in 2016. For example, host cells can be retrieved and engineered in the lab to “correct” conditions like sickle-cell disease. From there, the hope is that a wider variety of genetic disorders can be tackled, as well as other genome engineering to induce resistance to pathogens such as HIV. While it may be a few years before these therapies are available on the market, the disruption is happening now, and industry and governments will be forced to make big decisions on how to brace for CRISPR’s inevitable game changing impact.
Where Are They Now
In June 2016 a federal biosafety and ethics panel gave to go-ahead for the first ever clinical trial using CRISPR-Cas9. The trial is currently underway in China for patients with stage IV metastatic non-small cell lung cancer. Two clinical trials with CRISPR-Cas9 technology are in the pipeline in the United States. One of the two said trials involves CRISPR use to target three types of cancer: myeloma, sarcoma, and melanoma. This trial was on track for commencement in 2018, though its clinical trial status is still labeled as recruiting. Other moves to use in humans have been incredibly slow, due in part to an FDA pause on the second phase I/II in-human trial. Set to investigate CRISPR use in patients suffering from sickle cell disease, the trial was delayed in May 2018. Though the U.S. trial remains in limbo, its European counterpart was unaffected by the FDA decision and kicked-off in August 2018.