Ethical Issues Regarding CRISPR-mediated Genome Editing Zabta Khan Shinwari1,2*, Faouzia Tanveer1 and Ali Talha Khalil1 1Department of Biotechnology, Quaid-i-Azam University, Islamabad. 2Pakistan Academy of Sciences, Islamabad, Pakistan. *Correspondence: [email protected] htps://doi.org/10.21775/cimb.026.103 Abstract Introduction CRISPR/Cas9 has emerged as a simple, precise Te quest for introducing the site-specifc changes and most rapid genome editing technology. With in the DNA sequence began when DNA was frst a number of promising applications ranging from discovered. Progress in genome engineering tech- agriculture and environment to clinical therapeu- nologies began in 1990s now reaching to a highly tics, it is greatly transforming the feld of molecular advanced, easy, economical and sophisticated biology. However, there are certain ethical, moral method for editing genomes called CRISPR/Cas9. and safety concerns related to the atractive applica- CRISPR (Clustered Regularly Interspaced Palin- tions of this technique. Te most contentious issues dromic Repeats) technology does not arrive as a concerning human germline modifcations are the breakthrough technology for editing the genomes challenges to human safety and morality such as risk but other genome editing platforms like TALENS of unforeseen, undesirable efects in clinical appli- (Transcription Activator-Like Efector Nucleases) cations particularly to correct or prevent genetic and ZFN (Zinc Finger Nucleases) were in use for diseases, mater of informed consent and the risk of some time but have lost their popularity because exploitation for eugenics. Stringent regulations and of their complexity, expensiveness and time con- guidelines as well as worldwide debate and aware- sumption (Carroll and Charo, 2015; Doudna and ness are required to ensure responsible and wise use Charpentier, 2014; Hsu et al., 2014; Jinek et al., of CRISPR mediated genome editing technology. 2012). Te aforementioned techniques require Tere is a need for an extensive dialogue among protein engineering while CRISPR needs a guide scientists, ethicists, industrialists and policy makers RNA molecule that recognize the target sequence on its societal implications. Te opinion of diferent (Caplan et al., 2015). Te genome engineering tools elements of the society including the general public ofer promising advances in medicine, healthcare, as well as religious scholars is also critical. In coun- agriculture and food. CRISPR/Cas9 has brought a tries with existing legislative framework, it might revolution in the biological innovations. Tis tech- be appropriate to allow CRISPR-based research to nology can be used to treat the genetically inherited proceed with proper justifcation. However, much diseases by correcting the responsible mutation, anticipated future clinical applications must be analysing cancer progression and genetic rearrange- strictly regulated with newly established regula- ments (Doudna and Charpentier, 2014). Despite tions. the wide array of applications, ethicist raises serious Curr. Issues Mol. Biol. Vol. 26 104 | Shinwari et al. reservations about the CRISPR ability to easily Te present review discusses the ethical concerns modify the human germline cells, making these related to this new technology with special empha- changes transmitable to the progeny. sis on its possibilities and concerns on human CRISPR was initially discovered in the genome germline modifcations. It urges the need for an of E. coli by Japanese researchers in 1987 and extensive dialogue among scientists, ethicists, described as short direct repeats interspaced with industrialists and policy makers. Te opinion of dif- short sequences. Later on CRISPR was discov- ferent elements of the society including the general ered in many bacteria and archaea with a possible public as well as religious scholars is critical. role in gene regulation or DNA repair (Guy et al., 2004; Ishino et al., 1987; Makarova et al., 2002; Recent ethical debate: from where it Mojica et al., 2000). In 2005, it was discovered that started many spacer sequences that are accompanied with Te rapidly expanding scope of applications of CRISPRs were the derivatives of plasmid and viral CRISPR/Cas9 is incredible. It has provided a sequences (Bolotin et al., 2005). It was proposed number of possibilities in molecular biology by various research groups that CRISPR/Cas9 research, e.g. to turn of or on genes for studying has a possible role in adaptive immunity and this their function or to induce mutations in cells to proposition was confrmed later on in 2007 by study how and why cells become cancerous. It researchers working on Streptococcus thermophilus. can be used to alter genes in plants and animals In 2008, Brouns et al., in a study published in Sci- to create drought resistant crops or make police ence, showed that Cas proteins interfere with the dogs become more muscular. Ten comes a rather multiplication of a virus inside prokaryotes (E. contentious application to permanently modify the coli), while in the same year the DNA-targeting human genome to eliminate the disease-causing ability of CRISPR/Cas9 was established (Brouns et mutations or even enhance or introduce desired al., 2008; Marrafni and Sontheimer, 2008). (For characteristics in children by adding useful genes. a comprehensive history and mechanism which is Tough the idea of genetically modifed humans behind the scope of this review we recommend ‘Te and designer babies has been popular for a long new frontier of genome engineering with CRISPR/ time in both science and fction, CRISPR provided Cas9’ by Doudna et al., 2014.) a reasonable tool to turn this long cherished dream into a reality (le Page, 2015). Genomic changes made in the non-reproductive cells are not herit- Ethical issues regarding CRISPR able but if alterations are done to the germ cells technology (that develop into eggs, sperms or embryos), they Te rapidly growing technology of genome editing, can be passed to the ofspring. Te great accom- CRISPR/Cas9, is transforming the feld of molecu- plishment of CRISPR lies in the fact that it can be lar biology enabling scientists to make desired easily and precisely used in both reproductive and changes in DNA in a variety of organisms. Soon non-reproductive cells (Doudna, 2015). afer it was introduced in 2012, it has been quickly Until now, altering genes in humans was limited adopted due to ease of its use and simplicity. It is to gene therapy in which DNA modifcations were being considered for a variety of applications from inheritable. With accuracy and efciency of an agriculture to clinical therapeutics including human editor that could transfer the changes to the next germline alterations to correct genetic diseases generation, CRISPR has renewed the debate about (Carroll and Charo, 2015). Although the ethical human germline modifcations. With the advent debate on human genetic modifcations is not new of this technology, there was a sudden surge of (as mentioned previously), however, CRISPR/ genome editing experiments across the kingdom of Cas9-mediated genome editing has given it a new life, but mainly restricted to organisms other than edge. Owing to unpredictable and far reaching humans. Recently, there were also speculations that consequences associated with atractive applica- several scientists are secretly using this technology tions of this technology, a comprehensive dialogue on human embryos. In April 2015, research involv- is needed on its ethical and societal implications. ing CRISPR-based gene editing in human embryos Curr. Issues Mol. Biol. Vol. 26 CRISPR-mediated Genome Editing Ethical Issues | 105 appeared in an online journal ‘Protein and Cell’. Tis be edited. Tese made-to-order proteins may take study, done by a group of Chinese scientists (Liang years to make. In comparison, CRISPR simply et al., 2015) fanned the fames of ethical contro- requires a complementary RNA to bind the target versy on human germline alterations and triggered DNA taking only a few days to make. Tis is why a serious debate on issues such as how soon the CRISPR became popular as an efcient editing technology will be able to produce designer babies. technique among the scientists all over the world. Although the experiment was done on non-viable It is feared that with a gene editing technology like embryos meaning that they could not develop into CRISPR which can make changes in DNA efort- a live baby, it provided a proof of concept that, with lessly, the chances of things going wrong will also be litle tinkering of the CRISPR enzymes, the tech- larger. For example, the plants given characteristics nology might be someday successfully used on live like drought resistance or fast growth may become embryos (Krishan et al., 2015; Sharma and Scot, invasive weeds. Te most dreaded situation is that 2015). In general, apart from apprehensions related the technology may be used to produce a bio- to human genome, some environmental concerns weapon such as engineering an infectious pathogen have also been identifed as per CRISPR-mediated that infect humans or crops (Sarchet and Le Page, modifcations in plants such as crop improvement. 2015). It is very important to underline the regula- tory norms for the application of CRISPR. Safety Major concerns and security measures should be developed to con- trol any organism that can induce environmental Of-target mutations damage (Oye et al., 2014). Of-target mutations is one of the major concerns raised about the CRISPR/Cas9 genome engi-