Future of breeding by genome editing is in the hands of regulators (original) (raw)

Advances in genome editing for improved animal breeding: A review

Since centuries, the traits for production and disease resistance are being targeted while improving the genetic merit of domestic animals, using conventional breeding programs such as inbreeding, outbreeding, or introduction of marker-assisted selection. The arrival of new scientific concepts, such as cloning and genome engineering, has added a new and promising research dimension to the existing animal breeding programs. Development of genome editing technologies such as transcription activator-like effector nuclease, zinc finger nuclease, and clustered regularly interspaced short palindromic repeats systems begun a fresh era of genome editing, through which any change in the genome, including specific DNA sequence or indels, can be made with unprecedented precision and specificity. Furthermore, it offers an opportunity of intensification in the frequency of desirable alleles in an animal population through gene-edited individuals more rapidly than conventional breeding. The specific research is evolving swiftly with a focus on improvement of economically important animal species or their traits all of which form an important subject of this review. It also discusses the hurdles to commercialization of these techniques despite several patent applications owing to the ambiguous legal status of genome-editing methods on account of their disputed classification. Nonetheless, barring ethical concerns gene-editing entailing economically important genes offers a tremendous potential for breeding animals with desirable traits. Keywords: animal breeding, clustered regularly interspaced short palindromic repeats /Cas9, genome editing, transcription activator-like effector nuclease, zinc finger nucleases.

Thanks to Genome Editing: A Tool for Genomic Revolution

Today plant breeding technologies are driven by modern biotechnology tools to speed up the crop improvement programmes. Technological advancement is the key for novel biotechnological research. Programmable nucleases, such as Zinc-Finger Nucleases (ZFNs), Transcription Activator-Like Effector Nucleases (TALENs) and the Clustered Regularly-Interspaced Short Palindromic Repeat/CRISPR-associated (CRISPR/Cas), has revolutionized genome editing in plants, paving the way for novel applications in crop improvement. This review describes recent advances in genome editing, covering the underlying principles and molecular mechanism.

Genome editing and beyond: what does it mean for the future of plant breeding?

Planta

Main conclusion Genome editing offers revolutionized solutions for plant breeding to sustain food production to feed the world by 2050. Therefore, genome-edited products are increasingly recognized via more relaxed legislation and community adoption. Abstract The world population and food production are disproportionally growing in a manner that would have never matched each other under the current agricultural practices. The emerging crisis is more evident with the subtle changes in climate and the running-off of natural genetic resources that could be easily used in breeding in conventional ways. Under these circumstances, affordable CRISPR-Cas-based gene-editing technologies have brought hope and charged the old plant breeding machine with the most energetic and powerful fuel to address the challenges involved in feeding the world. What makes CRISPR-Cas the most powerful gene-editing technology? What are the differences between it and the other genetic engineering/breeding techni...

Genome Editing in Agriculture: Technical and Practical Considerations

International Journal of Molecular Sciences, 2019

The advent of precise genome-editing tools has revolutionized the way we create new plant varieties. Three groups of tools are now available, classified according to their mechanism of action: Programmable sequence-specific nucleases, base-editing enzymes, and oligonucleotides. The corresponding techniques not only lead to different outcomes, but also have implications for the public acceptance and regulatory approval of genome-edited plants. Despite the high efficiency and precision of the tools, there are still major bottlenecks in the generation of new and improved varieties, including the efficient delivery of the genome-editing reagents, the selection of desired events, and the regeneration of intact plants. In this review, we evaluate current delivery and regeneration methods, discuss their suitability for important crop species, and consider the practical aspects of applying the different genome-editing techniques in agriculture.

Genome editing in crop improvement: Present scenario and future prospects

Review paper, 2017

Genome editing refers to a process by which a specific chromosomal sequence is changed. The edited chromosomal sequence may comprise an insertion of at least one nucleotide, a deletion of at least one nucleotide, and/or a substitution of at least one nucleotide. Genome editing is a relatively new technology that is gaining importance as a tool for crop improvement because of its advantages over routinely used methods of genetic engineering. Genome-editing technology is precise and efficient. Genome editing is now considered a safe technique because no foreign sequences are left behind in the final genome-edited organism (GEO). Genome editing involves the induction of double-stranded breaks (DSBs) at specific sites of DNA, which turns on endogenous repair mechanisms—homology-dependent repair (HDR)—when homologous sequences are present, and nonhomologous end-joining (NHEJ) in the absence of homologous sequences. During repair, site-specific mutations are produced. A range of molecular tools for inducing DSBs at specific sites of a genome is available with genome editors. One category of such molecular scissors include engineered and programmable site-specific nucleases (SSNs), such as meganucleases (MNs), also known as homing nucleases (HNs), zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and RNA-guided nuclease (RGN) systems, the most widely used RGN being the clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated system 9 (CRISPR/Cas9), and DNAguided nuclease (DGN) system, i.e., NgAgo (an acronym for Natronobacterium gregoryi Argonaute). Transposons and Group II intron retro-transposition have also been employed in genome editing. Some new genome-editing approaches have also emerged under the umbrella of triplex technology, which are based on antisense technology and make use of diverse types of oligonucleotide-linked nucleases, triplex-forming oligonucleotides, nucleic acid analogs, peptide nucleic acids, and aptamers for providing homologous sequences for HDR. Some engineered animal viruses such as lentiviruses, adeno-associated viruses, recombinant adeno-associated viruses, and adenoviruses (AdVs) and plant viruses such as RNA viruses, tobacco rattle virus (TRV), and single-stranded DNA (ssDNA) viruses called geminiviruses have been used as genome-editing devices that act as delivery vehicles of SSNs ...

Genome editing for crop improvement: Challenges and opportunities

GM crops & food, 2015

Genome or gene editing includes several new techniques to help scientists precisely modify genome sequences. The techniques also enables us to alter the regulation of gene expression patterns in a pre-determined region and facilitates novel insights into the functional genomics of an organism. Emergence of genome editing has brought considerable excitement especially among agricultural scientists because of its simplicity, precision and power as it offers new opportunities to develop improved crop varieties with clear-cut addition of valuable traits or removal of undesirable traits. Research is underway to improve crop varieties with higher yields, strengthen stress tolerance, disease and pest resistance, decrease input costs, and increase nutritional value. Genome editing encompasses a wide variety of tools using either a site-specific recombinase (SSR) or a site-specific nuclease (SSN) system. Both systems require recognition of a known sequence. The SSN system generates single or...