Gene drive used in mammals for the first time. Possible effects of the genome modification of entire species
Could we change natural design without mayors consequences?
Gene drive technology allows genome of entire species to be modified, has been used for the first time in mammals (mice). The article has not yet been published, but it can already be read on the online preprint server bioRꭓiv , and many media have reported the news, among them Nature and Science.
Gene drive is a natural mechanism by which, occasionally, a certain gene eludes the laws of Mendelian inheritance, so that it will be transmitted to the offspring in almost 100% of cases, instead of the usual probability of 50%. Thus, the trait associated with the gene spreads rapidly in a population. These are so-called “selfish” genes. The genome editing tool CRISPR allows gene drives to be developed à la carte to transmit certain genetic characteristics in a population, for example, to transmit lethal genes between malaria-carrying mosquitoes. The strategy consists of introducing the CRISPR system together with the desired mutation in a chromosome. CRISPR cuts the other chromosome of the pair and copies the mutation introduced so that both chromosomes have it. This means that the mutation will be transmitted to the offspring, where it will also replace the allele of the other progenitor, ensuring transmission of the desired trait from generation to generation.
The study cited describes the development of gene drives in mice. The study objective was basic, to evaluate the efficacy of this technology in mammals. The investigators developed a gene drive to transmit the mutation that gives white pelage. Although the mutation was not always copied correctly, and only worked in female embryos, this is undoubtedly a major advance in the area.
In the opinion of our Bioethics Observatory at UCV, the main concerns in this respect are that, in the event that there is eventual release of the modified organisms into the natural environment, the gene drive could spread uncontrollably, the ecosystem could become unbalanced, or this technology could be used for malicious purposes. It is, therefore, necessary to design safety mechanisms that allow controlled use of gene drive and to establish adequate regulations in this respect.