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CRISPR-Cas9 mediated gene-editing mechanisms. A single guide RNA (sgRNA) recognizes a genomic region followed by 5'-NGG-3' PAM sequence, which recruits the Cas9 DNA endonuclease. This introduces a double-stranded break that is repaired by (i) non-homologous end joining (NHEJ), an error prone pathway that can result in the creation of Indels that can disrupt the gene, or by (ii) homology directed repair (HDR) in the presence of a donor construct.
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Since its emergence in 2012, the genome editing technique known as CRISPR-Cas9 and its scientific use have rapidly expanded globally within a very short period of time. The technique consists of using an RNA guide molecule to bind to complementary DNA sequences, which simultaneously recruits the endonuclease Cas9 to introduce double-stranded breaks...
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Since its emergence in 2012, the genome editing technique known as CRISPR-Cas9 and its scientific use have rapidly expanded globally within a very short period of time. The technique consists of using an RNA guide molecule to bind to complementary DNA sequences, which simultaneously recruits the endonuclease Cas9 to introduce double-stranded breaks...
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... These bans remain in effect until there is a consensus on the circumstances under which gene editing is deemed beneficial and where it crosses ethical boundaries. This issue is debated by many major organizations, including the World Health Organization (WHO) and the United Nations Educational, Scientific and Cultural Organization (UNESCO) (Cribbs et al., 2017). To date, 19 countries have completely banned germline cell editing and clinical trials involving CRISPR. ...
... Beyond neurotoxicity, CRISPR/Cas9 might exhibit systemic toxic effects [115]. The immunogenicity of the Cas9 protein, typically derived from bacteria, poses a risk of eliciting an adverse immune response, potentially leading to systemic inflammation or autoimmune reactions [95,116,117]. The repeated administration of CRISPR components could exacerbate these effects, necessitating the development of delivery systems that minimize immune recognition [118,119]. ...
This scoping review examines the use of CRISPR/Cas9 gene editing in glioblastoma (GBM), a predominant and aggressive brain tumor. Categorizing gene targets into distinct groups, this review explores their roles in cell cycle regulation, microenvironmental dynamics, interphase processes, and therapy resistance reduction. The complexity of CRISPR-Cas9 applications in GBM research is highlighted, providing unique insights into apoptosis, cell proliferation, and immune responses within the tumor microenvironment. The studies challenge conventional perspectives on specific genes, emphasizing the potential therapeutic implications of manipulating key molecular players in cell cycle dynamics. Exploring CRISPR/Cas9 gene therapy in GBMs yields significant insights into the regulation of cellular processes, spanning cell interphase, renewal, and migration. Researchers, by precisely targeting specific genes, uncover the molecular orchestration governing cell proliferation, growth, and differentiation during critical phases of the cell cycle. The findings underscore the potential of CRISPR/Cas9 technology in unraveling the complex dynamics of the GBM microenvironment, offering promising avenues for targeted therapies to curb GBM growth. This review also outlines studies addressing therapy resistance in GBM, employing CRISPR/Cas9 to target genes associated with chemotherapy resistance, showcasing its transformative potential in effective GBM treatments.
... Editing even a single gene could have unforeseen ripple effects on the entire genome, leading to unintended consequences that may manifest in future generations [33]. The long-term effects of such alterations are largely unknown, and the potential for irreversible harm to individuals, families, and entire populations raises profound ethical dilemmas about the risks we are willing to take with the genetic heritage of humanity [34]. ...
This article extends an exploration into renewed ethico-legal perspectives of genome editing technologies, examined from an evolved conceptualization of eugenics in contemporary human reproduction. Whilst the ethico-legal conundrums presented by genome-editing technologies in various aspects of modern medicine have thus far inspired a comprehensive trove of academic scholarship—and notwithstanding the World Health Organization’s (WHO) publication of guidelines on human genome editing in 2021—the legislative landscape for these technologies remain relatively unchanged. Accordingly, this paper presents the unresolved problematic questions that still require significant reflection. First, the paper highlights these questions, which primarily center around the tension between reproductive autonomy and the legal governance of reproductive/genome editing technologies by a democratic state. Secondly, the paper interrogates the evolved conceptualization of eugenics, exercised on the part of prospective parents as part of reproductive autonomy. By this, the paper predicates that it indirectly reinforces societal and systemic problems of discrimination and “othering”, increasing reproductive inequalities in excluded communities. Thirdly, the paper attempts to offer narratives of intersectionality as a facilitating tool in a continuing dialogue to build belonging, foster a healthy and balanced exercise of reproductive autonomy, and increase reproductive equalities.
... An approach that has recently been tested for the treatment of both genetic and nongenetic disorders is genome editing [140,141]. Its techniques include zinc finger nuclease, transcription activator-like effector nuclease and Cas9 nuclease associated with clustered regularly interspaced short palindromic repeats (CRISPR) [141]. ...
... An approach that has recently been tested for the treatment of both genetic and nongenetic disorders is genome editing [140,141]. Its techniques include zinc finger nuclease, transcription activator-like effector nuclease and Cas9 nuclease associated with clustered regularly interspaced short palindromic repeats (CRISPR) [141]. In the context of ALS, the last one seems to be the most promising, as its functionality is increasingly being tested in clinical trials. ...
Gene therapy is defined as the administration of genetic material to modify, manipulate gene expression or alter the properties of living cells for therapeutic purposes. Recent advances and improvements in this field have led to many breakthroughs in the treatment of various diseases. As a result, there has been an increasing interest in the use of these therapies to treat motor neuron diseases (MNDs), for which many potential molecular targets have been discovered. MNDs are neurodegenerative disorders that, in their most severe forms, can lead to respiratory failure and death, for instance, spinal muscular atrophy (SMA) or amyotrophic lateral sclerosis (ALS). Despite the fact that SMA has been known for many years, it is still one of the most common genetic diseases causing infant mortality. The introduction of drugs based on ASOs—nusinersen; small molecules—risdiplam; and replacement therapy (GRT)—Zolgensma has shown a significant improvement in both event-free survival and the quality of life of patients after using these therapies in the available trial results. Although there is still no drug that would effectively alleviate the course of the disease in ALS, the experience gained from SMA gene therapy gives hope for a positive outcome of the efforts to produce an effective and safe drug. The aim of this review is to present current progress and prospects for the use of gene therapy in the treatment of both SMA and ALS.
... Clinical trials are already underway for CRISPR-Cas9 applications to eliminate sickle-cell anaemia, hereditary blindness, and cancer, to name just a few (Doudna & Charpentier, 2014;Ledford & Calloway, 2020;Moss, 2014;Stein, 2019). Since CRISPR technology can be used to add, edit, or replace genes, however, such applications can be both transformative and controversial (Cribbs & Perera, 2017;Delhove et al., 2020;Doudna & Sternberg, 2018;Howard et al., 2018). A recent case in China, for example, involved the combined use of CRISPR technology and assisted reproductive technologies to edit the DNA of human embryos in a lab setting. ...
... Off-target gene mutation could potentially result in insertional mutagenesis and gene mutation [19]. Bioethicists and researchers suggest that genome editing is new and unpredictable technology, and little is known about gene regulation and mechanisms of embryonic development; therefore, the consequences of germline therapy can be fatal [20]. Despite the fact that CRISPR/Cas proves to be an efficient tool for clinical somatic use, it has not reached the stage to be utilized in human genome editing for clinical reproductive purposes. ...
One of the most important technologies in modern medicine is gene therapy, which allows therapeutic genes to be introduced into cells of the body. The approach involves genetics and recombinant DNA techniques that allow manipulating vectors for delivery of exogenous material to target cells. The efficacy and safety of the delivery system are a key step towards the success of gene therapy. Somatic cell gene therapy is the easiest in terms of technology and the least problematic in terms of ethics. Although genetic manipulation of germline cells at the gene level has the potential to permanently eradicate certain hereditary disorders, major ethical issues such as eugenics, enhancement, mosaicism, and the transmission of undesirable traits or side effects to patients’ descendants currently stymie its development, leaving only somatic gene therapy in the works. However, moral, social, and ethical arguments do not imply that germline gene therapy should be banned forever. This review discusses in detail the current challenges surrounding the practice of gene therapy, focusing on the moral arguments and scientific claims that affect the advancement of the technology. The review also suggests precautionary principles as a means to navigate ethical uncertainties.
... By targeting germline cells of experimental animals, precise transgenic and KO models can be generated much more quickly than previous methods (Williams et al., 2018). However, many significant technical and biologic hurdles remain before gene editing can be considered for clinical use in orthopaedics (Cribbs and Perera, 2017;Lino et al., 2018). The low efficiency of KI modifications, off-target DNA cleavage and template insertion, immune recognition of bacterial Cas proteins, and long-term safety are all major concerns . ...
In orthopaedics, gene-based treatment approaches are being investigated for an array of common -yet medically challenging- pathologic conditions of the skeletal connective tissues and structures (bone, cartilage, ligament, tendon, joints, intervertebral discs etc.). As the skeletal system protects the vital organs and provides weight-bearing structural support, the various tissues are principally composed of dense extracellular matrix (ECM), often with minimal cellularity and vasculature. Due to their functional roles, composition, and distribution throughout the body the skeletal tissues are prone to traumatic injury, and/or structural failure from chronic inflammation and matrix degradation. Due to a mixture of environment and endogenous factors repair processes are often slow and fail to restore the native quality of the ECM and its function. In other cases, large-scale lesions from severe trauma or tumor surgery, exceed the body’s healing and regenerative capacity. Although a wide range of exogenous gene products (proteins and RNAs) have the potential to enhance tissue repair/regeneration and inhibit degenerative disease their clinical use is hindered by the absence of practical methods for safe, effective delivery. Cumulatively, a large body of evidence demonstrates the capacity to transfer coding sequences for biologic agents to cells in the skeletal tissues to achieve prolonged delivery at functional levels to augment local repair or inhibit pathologic processes. With an eye toward clinical translation, we discuss the research progress in the primary injury and disease targets in orthopaedic gene therapy. Technical considerations important to the exploration and pre-clinical development are presented, with an emphasis on vector technologies and delivery strategies whose capacity to generate and sustain functional transgene expression in vivo is well-established.
... Clinical trials are already underway for CRISPR-Cas9 applications to eliminate sickle-cell anaemia, hereditary blindness, and cancer, to name just a few (Doudna & Charpentier, 2014;Ledford & Calloway, 2020;Moss, 2014;Stein, 2019). Since CRISPR technology can be used to add, edit, or replace genes, however, such applications can be both transformative and controversial (Cribbs & Perera, 2017;Delhove et al., 2020;Doudna & Sternberg, 2018;Howard et al., 2018). A recent case in China, for example, involved the combined use of CRISPR technology and assisted reproductive technologies to edit the DNA of human embryos in a lab setting. ...
... Gene-editing technologies such as CRISPR-Cas9 offer some promise in this regard. 24,25,26 A reliable predictive genetic marker for DC or periodontitis does not currently exist, but many candidate genes have been proposed. 17,18,19 Moreover, DC and periodontitis develop as a result of gene-environmental interaction, 17,18,19,20,27,28 suggesting that gene editing offers a potential therapeutic avenue in dentistry, in addition to behavioural enhancement approaches. ...
Oral diseases such as dental caries (DC) and periodontitis are widely prevalent, and existing approaches to managing these conditions have only a limited effect. Accordingly, there is growing interest in the development of novel biological interventions (including, among others, CRISPR-Cas9) that might, in the future, be used to prevent the development of or cure these conditions. However, in addition to familiar concerns about using biological interventions in children who cannot provide valid consent, it is not clear whether the provision of these interventions would fall within the proper domain of dentistry. In this opinion paper, we defend the view that the provision of reasonably safe and effective novel biological interventions aimed at preventing DC and periodontitis should be understood to fall within the proper domain of dentistry. To do so, we first argue that their use would be consistent with existing practice in dentistry. We then argue that: i) they may substantially increase the recipient's wellbeing and future autonomy; and ii) that their use could constitute a form of indirect preventative medicine by addressing a threat to systemic health.
... Many relevant, contemporary SSIs that are gaining increasingly more media attention are those concerning genetic engineering. These include issues such as the use of human gene therapy, genetic enhancement, germline and somatic cell modifications, and genetic screening technologies (Cribbs & Perera, 2017;Gunderson, 2007;Hammond, 2010;Wenz, 2005). Most recently, the development of a genome editing technology, CRISPR/Cas9, brought these issues to the forefront of public discourse. ...
... Of particular interest is the potential to edit germline cells. For example, a Chinese scientist recently claimed to have modified human embryos (germline cells) to be HIV resistant (Cribbs & Perera, 2017;Krimsky, 2019). Another concern is that the tool will be used for nonmedical enhancements. ...
... Eugenics has traditionally been defined as applying science to "improve the genetic composition of a population through controlling reproduction" and has historically been associated with political agendas that violate human rights and promote social inequality based on wealth, mental capabilities, and race (Garver & Garver, 1991;Subramaniam, 2014, p. 46). The potential application of CRISPR/Cas9 technology to the manipulation of germline cells and embryos makes this new eugenics a realistic prospect (Cribbs & Perera, 2017;Friedmann, 2019;Vizcarrondo, 2014), and we expected it to be discussed in our students' responses. Although the idea that nonmedical enhancement smacks of a "new eugenics" resonated with students, fewer students from Level 1 used eugenics in their arguments compared to Level 2 and 3 students (Vizcarrondo, 2014). ...
Consideration of socioscientific issues (SSIs) promotes the development of moral and sociocultural perspectives that encourage a rich understanding of the nature of science. The use of moral reasoning to approach SSIs is known to influence how students justify arguments and persuade others; less is known about how student moral reasoning is influenced by both content knowledge and demographic identities. We performed an exploratory study to investigate how students use moral reasoning when considering an SSI about the use of CRISPR/Cas9 technology for nonmedical enhancement in humans. Using content analysis, we examined written responses from 279 undergraduate students from three content knowledge levels and a variety of demographic populations (socioeconomic, gender, and first‐generation status). We identified instances of consequence and principle‐based moral reasoning and categorized commonly employed moral considerations under these broad themes. Students opposed nonmedical enhancement with CRISPR/Cas9 technology and perceived it as fraught with moral controversy primarily related to eugenics, equity, diversity, risk, and the authority of nature. Content knowledge level, gender, socioeconomic status, and first‐generation status influenced which moral considerations were employed by students and these carried interaction effects that indicate complex relationships between content knowledge level and demographic variables. We suggest more explicit instruction about complex societal issues linked to the history of science and genetic engineering, such as eugenics and inequity, and further investigation of moral perspectives for students from lower socioeconomic backgrounds and underrepresented groups so that these perspectives can be integrated into curricula to foster diverse classroom environments.
