Recommended Scientific Publications
- Álvarez et al (2022). TP53-dependent toxicity of CRISPR/Cas9 cuts is differential across genomic loci and can confound genetic screening, Nature Communications (2022).
- Papathasnasiou et al. (2021). Whole chromosome loss and genomic instability in mouse embryos after CRISPR-Cas9 genome editing. Nature Communications
- Höijer et al. (2021). CRISPR-Cas9 induces large structural variants at on-target and off-target sites in vivo that segregate across generations. bioRxiv.
Kawall, K. (2021). Genome-edited Camelina sativa with a unique fatty acid content and its potential impact on ecosystems. Environmental
Sciences Europe, 33(1), 1-12. https://enveurope.springeropen.com/articles/10.1186/s12302-021-00482-2
- Ghosh et al. (2021). Inadvertent nucleotide sequence alterations during mutagenesis: highlighting the vulnerabilities in mouse transgenic technology. Journal of Genetic Engineering and Biotechnology, 19(1), 1-11.
- Liu et al. (2021). Global detection of DNA repair outcomes induced by CRISPR-Cas9. bioRxiv.
Hough, S. (Winter 2020). Runaway Biology: A Call for Conscientious Genome Editing with
- Kawall et al. (2020). Broadening the GMO risk assessment in the EU for genome editing technologies in agriculture. Environmental Science Europe.
- Zuccaro et al. (2020). Reading frame restoration at the EYS locus, and allele-specific chromosome removal after Cas9 cleavage in human embryos. bioRxiv.
- Liang et al. (2020). Frequent gene conversion in human embryos induced by double strand breaks. bioRxiv.
- Alanis-Lobato et al. (2020). Frequent loss-of-heterozygosity in CRISPR-Cas9-edited early human embryos. bioRxiv.
- Biswas et al. (2020). Investigation of CRISPR/Cas9-induced SD1 rice mutants highlights the importance of molecular characterization in plant molecular breeding. Journal of Genetics and Genomics.
- Weisheit et al. (2020). Detection of deleterious on-target effects after HDR-mediated CRISPR editing. bioRxiv
Murugan et al. (2020). CRISPR-Cas12a has widespread off-target and dsDNA-nicking effects.
Journal of Biological Chemistry, jbc-RA120.
- Skryabin et al. (2020). Pervasive head-to-tail insertions of DNA templates mask desired CRISPR-Cas9–mediated genome editing event. Science Advances, Vol 6, No 7
- Myskja et al. (2020). Non-safety Assessments of Genome-Edited Organisms: Should They be Included in Regulation? Science and Engineering Ethics
- Sansbury et al. (2019). Understanding the diversity of genetic outcomes from CRISPR-Cas generated homology-directed repair. Communications Biology 2 (458)
- Smits et al. (2019). Biological plasticity rescues target activity in CRISPR knock outs
- Mehta et al. (2019). Linking CRISPR-Cas9 interference in cassava to the evolution of editing-resistant geminiviruses. Genome Biol, 20(1), 80. doi: 10.1186/s13059-019-1678-3
- Norris et al. (2019). Template plasmid integration in germline genome-edited cattle
- Ono et al. (2019). Exosome-mediated horizontal gene transfer occurs in double-strand break repair during genome editing.
Owens et al. (2019). Microhomologies are prevalent at
Cas9-induced larger deletions. Nucleic acids research.
- Gelinsky, E. and Hilbeck, A. (2018). European Court of Justice ruling regarding new genetic engineering methods scientifically justified: a commentary on the biased reporting about the recent ruling
- Kosicki, M. et al. (2018). Repair of double-strand breaks induced by CRISPR–Cas9 leads to large deletions and complex rearrangements. Nature Biotechnology volume 36, pages 765–771.
- Lalonde, S. et al. (2017). Frameshift indels introduced by genome editing can lead to in-frame exon skipping. PLoS ONE 12(6): e0178700.
- Mou, H. et al. (2017). CRISPR/Cas9-mediated genome editing induces exon skipping by alternative splicing or exon deletion. Genome Biology, 18(1), 108.
- Schaefer, K. A. et al. (2017). Unexpected mutations after CRISPR-Cas9 editing in vivo. Nature methods, 14(6), 547-548.
- Sharpe, J. J., & Cooper, T. A. (2017). Unexpected consequences: exon skipping caused by CRISPR-generated mutations. Genome Biology, 18(1), 109.
- Shin, H. Y. et al. (2017). CRISPR/Cas9 targeting events cause complex deletions and insertions at 17 sites in the mouse genome. Nat Commun. 2017 May 31;8:15464.
- Kapahnke, M. et al. (2016). Random splicing of several exons caused by a single base change in the target exon of CRISPR/Cas9 mediated gene knockout. Cells, 5(4), 45.
Recommended Further Reading
- Legal opinion, Prof. Dr. Dr. Tade M. Spranger (2017): In-depth analysis of various European directives and regulations with regard to their potential to regulate environmental effects of New Technologies be-sides Genetic Engineering Law.
- Jonathan Latham PhD (2016): God's Red Pencil? CRISPR and The Three Myths of Precise Genome Editing
- ECNH (2016): New Plant Breeding Techniques - Ethical Considerations (DE, FR, IT)
- CEO (2016): Biotech lobby's push for new GMOs to escape regulation
- EcoNexus briefing (2015): Genetic Engineering in Plants and the "New Breeding Techniques (NBTs)". Inherent risks and the need to regulate
- Prof. Jack A. Heinemann (2015): Is Oligonocleotide directed mutagenesis (ODM) a regulated technique of genetic modification?
- BfN (2015): Legal Analysis of the applicability of Directive 2001/18/EC on genome editing technologies
- Prof. Dr. Ludwig Krämer (2015): Legal questions concerning new methods for changing the genetic conditions in plants
- GenØk (2015): Biosafety report: Current status of emerging technologies for plant breeding: Biosafety and knowledge gaps of site directed nucleases and oligonucleotide-directed mutagenesis
- Fact Sheet UCS (2015): How Investment in Classical Breeding Can Support Sustainable Agriculture
New Genetic Engineering Techniques
In the past decade, various new GM techniques have been developed. These include Oligonucleotide Directed Mutagenesis (ODM), Zinc Finger Nuclease Technology (ZFN) types -1, -2 and -3, TALENs, CRISPR-Cas9, Meganucleases, Cisgenesis & Intragenesis, Grafting, Agro-infiltration, RNA-dependent DNA methylation (RdDM), Reverse breeding, and more recently base editing and prime editing.
It is often claimed by the industry, some public-private research institutes and in the media, that genome editing techniques are more precise and hence safer than common transgenesis and that the products resulting from these techniques contain no foreign DNA and are thus not to be considered GMOs. What has become more precise with genome editing techniques such as CRISPR-Cas is where in the genome a double-strand break is inserted. What happens after the cut, how the cell repairs the double-strand break, and how a gene of interest is inserted, remains, however, still inadequately understood.
Hence, the process has been prone to errors, including the insertion of unwanted DNA-fragments and large DNA deletions or rearrangements, which can ultimately lead to proteins that are altered in their structure as reported in the scientific literature (so called on-target effects). Moreover, a growing number of studies have reported additional DNA cuts at further unintended places (off-target effects), although only a fragment of studies looks for such off-target effects. Furthermore, rarely discussed is that while the techniques have changed, the process of plant transformation has remained largely the same – a gene construct is introduced into a cell using a vector (commonly agrobacterium tumefaciens) or by particle bombardment – the risks basically remain the same as well. (See major publication by CSS and others on the issue)
Extension of Gene-Tech Moratorium
Critical Scientists Switzerland published a statement in response to the Federal consultation process on the extension of the Swiss gene technology moratorium.
The Critical Scienstists Switzerland welcome the planned extension of the moratorium. We fully agree with the Federal report on the planned extension that organisms produced with new gene editing technologies are subject to the current legislation on gene technologies (Gene Technology Act) and are regulated accordingly (precautionary principle, risk assessment, step-by-step procedure, labelling, and monitoring). Despite some inconsistencies of the Federal report highlighted in our statement, Critical Scientists Switzerland generally support the current government policy.
Open letter on new biotechnologies from the Latin American Union of Concerned Scientists with Society and Nature (UCCSNAL)
In their letter, UCCSNAL question the safety of CRISPR/Cas9 and other new biotechnologies as well as the influence of science in the decision-making process regarding the adoption of the new technologies. They fear that these technologies will further increase monopolistic powers over seeds, land grabbing and migration from the land and also have other, unanticipated impacts.
"The new technologies facilitate faster, more extensive changes in the genetic material of more organisms, and at lower cost", they argue.
UCCSNAL demands a halt of all experimentation in this field. Rather, science should be based on acroecological techniques and local knowledges.
Open letter (English)
Open letter (Spanish)
New genetic engineering: Old wine in a new bottle?
Is it or isn't it?
Cisgenesis, zinc finger nuclease technology, reverse breeding, oligonucleotide-directed mutagenesis etc – the field of new techniques is broad and complex. New techniques or adaptations of existing techniques are constantly being added. The current political discussion, and the debate within public authorities or critics of genetic engineering, mostly focus on whether a particular technique or the product derived from it should be classed as genetic engineering or not, using the definition of genetic engineering set out in Art. 2.2 of the Release Directive (2001/18/EC) as a basis. In order to avoid too much technical detail, it is helpful to offer an initial categorisation of techniques based on their respective approach.
Category 1: Despite all claims to the contrary: "Classic" genetic engineering
Many of the new techniques are not really new, but correspond to techniques that have been established for over 20 years. This applies to both the breeding process and end products. Presently, attempts are being made to describe these techniques and their resulting products as conventional forms of breeding. Sometimes this even employs arguments brought to bear by the critics of genetic engineering. It is argued, for example, that unlike transgenesis, cisgenesis does not cross the species barrier and that the same results could therefore also be achieved through conventional breeding. The methods of transformation, however, clearly do represent forms of genetic engineering (particle bombardment or Agrobacterium tumefaciens). Even if the new gene originates from a species compatible for cross-breeding, it is impossible to predict where it will be integrated in the genome. This is what constitutes the risk inherent in this technique, in contrast to conventional breeding.
This category particularly includes the following procedures: Cisgenesis, intragenesis, floral dip and the use of genetically modified scions. Grafting onto genetically modified rootstock for commercial growing (not just during the breeding process) also falls within this category. It is incorrect to claim that harvested products (such as apples) derived from a scion grafted onto a GM parent plant do not constitute GMO. It is possible, for example, that proteins from the GM rootstock are transported to the non-GM scion; the phenotype of the scion and its product could therefore be altered. We believe the position of the Central Commission for Biological Safety (Zentrale Kommission für die Biologische Sicherheit, ZKBS), as outlined in their statement, to be unjustified; this demands that only GM rootstock should be classified as GMO and not the resulting harvested products (ZKBS, 2012:10). Even if no traces of transgenic or cisgenic DNA are found in the product, the principle of process-based evaluation which currently prevails in Europe mandates that the entire organism should be regulated as GMO, both for the purpose of growing these organisms and for labelling the resulting harvested crops.