MIT Technology Review, a magazine belonging to the Massachusetts Institute of Technology published an article titled ‘First Human Embryos Edited in U.S’ on 26th of July 2017. The subtitle said ‘Researchers have demonstrated they can efficiently improve the DNA of human embryos’.
This news has attracted huge media attention and the original article became highly cited just within a few days of its publication.
A team of Researcher at Oregon Health and Science University, Portland, USA, led by Shoukhrat Mitalipov declared that they have successfully created the world’s first genetically modified embryos. The paper is not yet published and neither have the researchers shared any details with regards to their methodology and key results. But still, some basic information has been shared via this review. For example, the gene-editing technique CRISPR has been used on one-cell embryos generated from sperm donated by men having certain inheritable genetic mutations. And the target of the CRISPR was to chop off that mutation from the genome. There seems to have been over a dozen of successfully created genetically modified embryos using in vitro fertilization (IVF) method. The review describes the number as “many tens”. Another achievement seems to be the eluding of the off-target mutations which CRISPR is known to have resulted in, in the past. Yet another attribute is a significant reduction in mosaicism (the property or state of being composed of cells of two different genotype), wherein the effect of CRISPR is observed in some but not all cells. In spite of this milestone, one cannot observe or critically analyze on what was done differently to make this happen. There is no information on specific numbers, no information on the disease with which the donor males were suffering. But one key information coming out of this story is that these embryos were destroyed right after a few days of experiment and were not implanted in any womb!
Dr. Shoukhrat Mitalipov
Another reason why this news is popular is that this is the first time CRISPR has been used to edit human germline in the United States. The lead researcher, Shoukhrat Mitalipov, however, was born in Kazakhstan. In the past three groundbreaking studies reported were all from China. The most important one was in 2015 where an attempt was made to eliminate genes responsible for heritable blood disorder beta thalassemia, but the experiment had limited success besides mosaicism and unintended mutations.
Another point which must be taken into consideration is that for any such research to happen the law of the land plays a vital role. For example, In February 2017, the National Academy of Sciences recommended that germline modifications can be allowed only when the goal is to prevent the occurrence of a disease in a child but not to introduce desirable traits or abilities like higher intelligence. While some (shown in red) like Canada and the UK have an outright ban on human germline engineering.
Although this research is worthy of attention given that off target mutations and mosaicism were avoided nothing can be said with confidence until the paper is out.