Efficient allelic-drive in Drosophila

Guichard, Annabel; Haque, Tisha; Bobik, Marketta; Xu, Xiangru; Klanseck, Carissa; Kushwah, Raja Babu Singh; Berni, Mateus; Kaduskar, Bhagyashree; Gantz, Valentino M.; Bier, Ethan

doi:10.1038/s41467-019-09694-w

Cited by 62 publications

(114 citation statements)

References 36 publications

(37 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Here, using a split-drive design, we were able to carefully assess the effects of timing, expression and inheritance of Cas9 on both homing and cleavage efficiencies. As reported previously, we found that maternal Cas9 protein deposition was sufficient to induce shadow drive (Guichard et al, 2019) in addition to high rates of F 1 somatic LOF mutations Lin and Potter, 2016;Oberhofer et al, 2018;Port et al, 2014). However, unexpectedly we found that embryonic expression of Cas9 was also sufficient to induce cleavage and homing.…”

Section: Somatic Expression Of Cas9 Results In High Mutagenesis Ratessupporting

confidence: 85%

“…Consistent with previous studies, we also found that maternal deposition of Cas9 protein into the embryo can result in both cleavage and homing in the germ cells (Guichard et al, 2019). In addition to this observation, we also found that paternal Cas9 protein deposition was not sufficient to induce either cleavage or homing, presumably due to the low quantities of Cas9 carried by the sperm into the egg.…”

Section: Resistant Alleles Accumulate Over Subsequent Generationssupporting

confidence: 92%

“…homing of GDe) in y-,w GDe /y+,w+ females. This conversion which occurs in the presence of Cas9 protein, but absence of inheritance of the Cas9 gene, was previously noted and termed "shadow drive" (Guichard et al, 2019). The remaining DSBs at w+ alleles were repaired by NHEJ and generated around 38% -23% w R2 alleles (Fig.…”

Section: Maternally Deposited Cas9 Is Sufficient To Induce Homing Of mentioning

confidence: 74%

See 2 more Smart Citations

Assessment of a split homing based gene drive for efficient knockout of multiple genes

Kandul

Liu

Buchman

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

Homing based gene drives (HGD) possess the potential to spread linked cargo genes into natural populations and are poised to revolutionize population control of animals. Given that hostencoded genes have been identified that are important for pathogen transmission, targeting these genes using guide RNAs as cargo genes linked to drives may provide a robust method to prevent transmission. However, effectiveness of the inclusion of additional guide RNAs that target separate host encoded genes has not been thoroughly explored. To test this approach, here we generated a split-HGD in Drosophila melanogaster that encoded a drive linked effector consisting of a second gRNA engineered to target a separate host encoded gene, which we term a gRNA-mediated effector (GME). This design enabled us to assess homing and knockout efficiencies of two target genes simultaneously, and also explore the timing and tissue specificity of Cas9 expression on cleavage/homing rates. We demonstrate that inclusion of a GME can result in high efficiency of disruption of its target gene during super-Mendelian propagation of split-HGD. However, maternal deposition and embryonic expression of Cas9 resulted in the generation of drive resistant alleles which can accumulate and limit the spread of such a drive. Alternative design principles are discussed that could mitigate the accumulation of resistance alleles while incorporating a GME.

show abstract

Section: Somatic Expression Of Cas9 Results In High Mutagenesis Ratessupporting

confidence: 85%

Section: Resistant Alleles Accumulate Over Subsequent Generationssupporting

confidence: 92%

Section: Maternally Deposited Cas9 Is Sufficient To Induce Homing Of mentioning

confidence: 74%

See 1 more Smart Citation

Assessment of a split homing based gene drive for efficient knockout of multiple genes

Kandul

Liu

Buchman

et al. 2019

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…2). Such phenomenon has been observed with gene drive constructs that were not inserted initially at the target site but at another position in the genome (Gantz and Bier 2015;Guichard et al 2019) . The probability of such an event will depend on the length of the flanking homology arms, their percentage of identity,the length of the DNA sequence in between and the position of the donor sequence relative to the cut site (Wang et al 2017) .…”

Section: Probability That the Gene Drive Cassette Inserts Near The Tamentioning

confidence: 72%

“…If the gene drive was designed to eliminate a target population, then it is more likely to eliminate the non-target species. The drive may also have unexpected effects, for example mosaicism due to perdurance of Cas9 expression (Guichard et al 2019) .…”

Section: Discussionmentioning

confidence: 99%

Evaluating the Probability of CRISPR-based Gene Drive Contaminating Another Species

Courtier‐Orgogozo

Danchin

Gouyon

et al. 2019

Preprint

View full text Add to dashboard Cite

The probability D that a given CRISPR-based gene drive element contaminates another, non-target species can be estimated by the following Drive Risk Assessment Quantitative Estimate (DRAQUE) Equation: D = ( hyb+transf).express.cut.flank.immune.nonextinct with hyb = probability of hybridization between the target species and a non-target species transf = probability of horizontal transfer of a piece of DNA containing the gene drive cassette from the target species to a non-target species (with no hybridization) express = probability that the Cas9 and guide RNA genes are expressed cut = probability that the CRISPR-guide RNA recognizes and cuts at a DNA site in the new host flank = probability that the gene drive cassette inserts at the cut site immune = probability that the immune system does not reject Cas9 -expressing cells nonextinct = probability of invasion of the drive within the populationWe discuss and estimate each of the seven parameters of the equation, with particular emphasis on possible transfers within insects, and between rodents and humans. We conclude from current data that the probability of a gene drive cassette to contaminate another species is not insignificant. We propose strategies to reduce this risk and call for more work on estimating all the parameters of the formula.

show abstract

An Exclusive Interview With CRISPR

McConnell

2019

AMA Journal of Ethics

View full text Add to dashboard Cite

This article chronicles a didactic encounter between an ethics-minded physician-scientist and a personified genome editing technology called clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated proteins, commonly abbreviated as CRISPR/Cas, or simply CRISPR. The interview considers clinically and ethically relevant questions about this technology related to patient safety, therapeutic efficacy, equitable access, and global governance of humanity's genetic legacy. PrologueJoe is an esteemed physician-scientist whose patients frequently inquire about "CRISPR therapies." Often curious about technological and ethical limits of human genome editing, they sometimes even want to discuss various futuristic applications, including nontherapeutic enhancements, which can make Joe feel slightly uncomfortable.With MD and PhD degrees from State University, Joe currently runs a practice and lab focused on gene editing. He believes CRISPR to be the future of medicine, once we figure out how to manage its risks. Late one night, CRISPR visits Joe in a dream state and posits that there is little to worry about and no apparent contradiction between any proposed uses and established ethical values.CRISPR: Call me CRISPR, if you insist, or use my preferred full title, clustered regularly interspaced short palindromic repeats and CRISPR-associated proteins. I spent something like a billion years of dedicated service in the phage wars, 1 endowing bacteria with immunological memory and defense. Recently, I was plucked from obscurity and made a favorite plaything of the dominant metazoan on the planet. Now I'm not quite sure what to make of myself anymore, whether savior, rogue, or something else entirely. Join me as I explore my illustrious past, my inimitable present, and my immeasurable future. What can possibly go wrong? We'll get to that, spotlighting the inglorious villains, industrious heroes-and, above all, incredible me. I'll also offer my own unique approach to handling some pesky ethical questions.

show abstract

Efficient allelic-drive in Drosophila

Cited by 62 publications

References 36 publications

Assessment of a split homing based gene drive for efficient knockout of multiple genes

Assessment of a split homing based gene drive for efficient knockout of multiple genes

Evaluating the Probability of CRISPR-based Gene Drive Contaminating Another Species

An Exclusive Interview With CRISPR

Contact Info

Product

Resources

About