gene editing clinical trials in diseases such as Transthyretin amylodosis in which CRISPR is being used to delete genes in the patient liver, due to start in 2022. Many further projects are in discovery to develop treatments for a range of diseases including α1‐antitrypsin deficiency and Cystic Fibrosis.
Last and perhaps one of the most exciting applications of CRISPR in drug discovery is the potential to create highly sensitive, inexpensive, point‐of‐care diagnostics for the early detection of disease (Chen et al. 2018; Gootenberg et al. 2018; Myhrvold et al. 2018). It is widely accepted, particularly in Oncology, that the probability of patient survival from the disease increases with early disease detection. The creation of diagnostics that detect cancer in stage 1 rather than when symptomatic in stage 3 or 4 will transform our ability to treat and perhaps cure this disease. Two methods have been published, described as SHERLOCK and DETECTR, that offer the potential to create such sensitive DNA diagnostics. While in early development, the potential of these innovations is huge and are being applied more broadly, including for the creation of a diagnostic test for the SARS‐CoV2 virus.
1.5 Concluding Comments
Since the demonstration of the ability of CRISPR/Cas systems to precisely and efficiently edit gene sequences in 2012, CRISPR has become embedded as a routine technique in molecular and cell biology laboratories across the field. New industries have been created to supply CRISPR reagents and CRISPR‐edited cell and animal models to the research scientist, to develop CRISPR medicines and to create CRISPR diagnostics. The applications and impact of CRISPR in drug discovery are discussed at length within this book. Within eight short years, CRISPR has transformed our ability to identify and characterize the role of new drug targets in disease and to create the cell and animal models integral to identify and optimize drug candidates. With the rate of innovation in this field, we can look forward to the development of novel CRISPR systems that increase the efficiency and specificity of gene editing, to the development of transformative CRISPR therapies with the potential to cure severe genetic diseases and to the invention of highly sensitive diagnostics for the early identification and subsequent cure of many common diseases. As we move through the coming decades, the opportunity for CRISPR to improve human health remains enormous.
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2 Historical Overview of Genome Editing from Bacteria to Higher Eukaryotes
Marcello Maresca
Genome Engineering, Discovery Sciences, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
2.1 Introduction
Molecular cloning methods have been instrumental for the establishment of the biotechnological industry. The ability to clone any DNA sequence of interest into a DNA vector has been a key technology advancement toward the generation of cellular and animal model of disease and the development of biopharmaceuticals. Traditional molecular cloning methods mostly rely on restriction enzymes‐mediated digestion
