Bayer strikes patent deal with ERS Genomics

GenomeWeb, 17 May 2016,

Bayer has licensed the CRISPR/Cas9 patents held by ERS Genomics which will expand upon their preexisting collaboration with CRISPR Therapeutics.  ERS Genomics holds the rights to Emmanuelle Charpentier’s CRISPR patents.

Editing of human induced pluripotent stem cells with CRISPR/Cas9 has fundamentally altered the approach to biomedical research

Hockemeyer D., et. al. (2016) Cell Stem Cell.  5:573-586.

The use of human induced pluripotent stem cells(hiPSCs) has allowed researchers to study a variety of diseases and gene functions in non-cancerous cell lines. However the ability to alter the genetics of these cells has posed a significant challenge. With the advent of CRISPR/Cas9 gene editing, modification of hiPSCs has become almost routine.  The combination of these two technologies has changed how researchers study human genetics in a way that will fundamentally alter how scientists approach biomedical research.

Zika field test uses CRISPR/Cas9 to distinguish between Zika strains

Pardee, K. et. al., Cell (2016),,

Zika has proven challenging due to its close relation to other viruses such as Dengue. Pardee et al have developed a low cost field test that couples isothermal RNA amplification with toehold switch RNA sensors to detect Zika.  The assay provides a quick readout using a colorimetric change of the sensor.  By adding in a CRISPR/Cas9 component the researchers were able to provide an assay that can even distinguish between strains of Zika with single-base resolution.  Development of these types of tools should help researchers efficiently determine how quickly the Zika virus is spreading.

Science journalist Jennifer Kahn presents the benefits and problems of gene drives

Jennifer Kahn, TED, February 2016

Jennifer Kahn presented at TED 2016 on CRISPR gene drives.  Kahn covers the theory behind CRISPR gene drives and how they could be used to manage diseases such as malaria as well as invasive species like the Asian Carp.  By asking the question, “are we now gods?” she examines the ethics of gene drives as well as their risks and benefits. Ultimately Kahn makes the case that when confronted with diseases like malaria inaction could be worse.

Washington Grapples with a Thorny Question: What Is a GMO Anyway?

Mike Orcutt, May 26, 2016, MIT Technology Review

Gene editing technologies, such as CRISPR, have made it increasingly difficult to distinguish between traditionally bred and genetically modified crops leading to the need for new regulatory guidelines.  The National Academies of Science recently released a report providing guidelines for a new regulatory framework that judges the novelty of a crop and not the process under which it was created.  This is especially important as the USDA has recently stated that CRISPR edited crops will not be regulated like traditional GMOs.

Adaptation of CRISPR for use in neural tissue

25Emma Yasinki, GEN, May 25, 2016

CRISPR gene editing has now been used extensively to knock-in novel DNA sequences. However, as this mechanism relies in part on the cells native homologous recombination machinery, cells that don’t divide rapidly, such as neurons, have been difficult to modify.  Researchers have now developed a new technique coined SLENDR that uses CRISPR/Cas9 and in utero electroporation allowing transformation of prenatal models when the neural cells are still dividing thus allowing homology directed repair of double stranded breaks.

CRISPR/Cas9 has been adapted to aid in mapping of unknown genes

Catherine Offord, 5 May 2016,The Scientist,

Traditional gene mapping follows phenotypic traits through multiple generations and homologous recombination events.  Using the cells natural meiotic processes researchers are able to determine regions of the genome responsible for certain traits, however this process is limited since crossing over is a rare event and it is impossible to control where the event occurs.  Researchers have now used CRISPR/Cas9 to induce crossing over through HDR  to control where crossing over occurs.  Coupled with a GFP marker, the researchers were able to quickly identify a SNP in yeast responsible for manganese sensitivity.  Additional research is needed to adapt this technique to more complex systems such as human cell lines.

CRISPR/Cas9 outperforms both CRISPRi and traditional shRNA in a genome wide knockout screen to identify essential genes

Evers, B., et. al. Nature Biotechnology (2016)

High-throughput knockout screens have become an important tool in identifying essential genes.  Traditionally this process used shRNA to target genes with both CRISPR/Cas9 and CRISPRi currently emerging as alternatives.  To determine which type of screen produces the most reliable results with fewer off-target effects and low noise Evers et al compared the three technologies in RT-112 cells.  CRISPR/Cas9 was found to perform better than its inactive CRISPRi counterpart and traditional shRNA screens.

CRISPR based gene therapies may still be years away

Jocelyn Kaiser, Science

While gene editing techniques such as CRISPR/Cas9 have changed the way basic research is being conducted, widespread use of the technology in medical treatments could be years away.  As with previous promising gene therapies the largest obstacle is delivery of the required proteins into the organs of interest.    The repair of the mutations behind genetic disorders often necessitates the use of HDR, however as HDR has very low efficiencies most of the treated cells may end up being repaired by NHEJ, presenting a challenging obstacle to researchers.  While many gene therapists are excited for the potential of CRISPR/Cas9 technology, years of research are needed before it sees clinical application.