WBUR Boston sits down with Eric Lander to discuss CRISPR/Cas9

Radio Boston, WBUR Boston’s NPR News Station, 25 April 2016 http://radioboston.wbur.org/2016/04/25/eric-lander-crispr

WBUR Boston sits down with the Broad Institute’s Eric Lander to discuss how CRISPR/Cas9 technology works and the numerous potential applications.  He also responds to the controversy over his recent review article in Cell on the history of CRISPR and how the article could impact the patent fight between the Broad Institute and UC-Berkeley.

Researchers solve the crystal structure of Cpf1 in complex with CRISPR RNA

Dong, D., et. al. Nature (2016) 532:522-526 http://www.ncbi.nlm.nih.gov/pubmed/27096363

Researchers elucidated the crystal structure of the Cas9 functional analog Cpf1 in complex with crRNA at a 2.38Å resolution.  Cpf1 was isolated from Lachnospiraceae bacterium ND2006 and found to have a triangular  shape with a positively charged central channel.  Extensive intramolecular forces and Mg(H20)62+ stabilize  the Cpf1-crRNA structure.  The determination of this crystal structure will facilitate engineering of Cpf1 in order to improve its specificity and decrease off-target effects.

Scientists successfully edit chicken germ lines using CRISPR/Cas9

Dimitrov, L., et. al. Germline Gene Editing in Chickens by Efficient CRISPR-Mediated Homologous Recombination in Primordial Germ Cells. (2016) PLoS ONE 11(4): e0154303. doi:10.1371/journal.pone.0154303. http://www.ncbi.nlm.nih.gov/pubmed/27099923

Genetic modification of birds has proven challenging due limited access to fertilized zygotes.  German researchers used CRISPR/Cas9 to overcome this barrier.  Primordial germ cells were modified in vitro and subsequently introduced to the germ line.  The resulting offspring were modified at the targeted IgH gene demonstrating that editing chicken genomes is possible with CRISPR/Cas9.

US Government forms a committee to predict the future of biotechnology

Kelly Servick, Science Magazine, 19 April 2016, http://www.sciencemag.org/news/2016/04/us-looking-expert-panel-predict-future-gm-products

President Obama announced last July that the United Stated Government would be revising the decades old guidelines on how biotech products, including genetically modified crops and animals, would be regulated by the FDA, USDA, and EPA.  To assist this process, the National Academies of Sciences, Engineering, and Medicine has formed a committee composed of representatives from industry and academia to predict the types of biotechnologies that could be possible in the next decade.  CRISPR/Cas9 technology will be at the forefront of this discussion with the rulings of the committee released in December 2016.

CRISPR/Cas9 edited mushroom will not be regulated by USDA

Emily Waltz, 14 April 2016, Nature News, http://www.nature.com/news/gene-edited-crispr-mushroom-escapes-us-regulation-1.19754

Researchers at Pennsylvania State University have used CRISPR/Cas9 to knock out one of six polyphenol oxidase genes in the common white mushroom.  Polyphenol oxidases are a class of enzymes that cause browning in cut mushrooms.  By knocking out one polyphenol oxidase gene researchers were able to decrease the total polyphenol oxidase activity by approximately 30%, prolonging the shelf life of the mushroom.  Since this mushroom does not contain a transgene, the USDA has ruled that it does not fall under its regulations for genetically modified organisms.

Does the pursuit of patents harm University collaboration?

Jacob Sherkow, 13 April 2016, Nature http://www.nature.com/news/crispr-pursuit-of-profit-poisons-collaboration-1.19717

Before the Bayh-Dole Act of 1980 all inventions developed through the use of federal grants where the property of the federal government.  The passing of the Bayh-Dole act allowed public universities, small businesses, or other non-profits to patent inventions developed with federal funding.  Initially most universities did not actively pursue patents; however this has begun recently begun to change.  The most visible effort to acquire intellectual property is the CRISPR/Cas9 dispute between UC-Berkeley and the Broad Institute.  In a recent Nature Comment article, Jacob Sherkow explores how the changing patent landscape could impact research and collaboration at America’s universities.

2016 is on track for its second CRISPR/Cas9 IPO

Robert Weisman, Boston Globe, 11 April 2016 https://www.bostonglobe.com/business/2016/04/11/intellia-plans-ipo-strikes-deal-with-regeneron/LigZmVRwOWoDZv3klrGlfM/story.html

Cambridge startup Intellia Therapeutics Inc. filed Monday 11 April for an IPO seeking to raise $120 million.  Intellia Therapeutics also announced a collaboration with Regeneron Pharmaceuticals Inc., with Intellia receiving $75 million up front with the possibility for royalty payments if Regeneron successfully markets 10 gene-editing drugs developed from Intellia’s technology.

Editing out HIV from infected T-Cells using CRISPR/Cas9

Kaminski et al, Scientific Reports, (2016) 6:22555 http://www.ncbi.nlm.nih.gov/pubmed/26939770

While treatments for HIV have vastly improved in the last decades, HIV positive patients require a lifelong regiment of anti-viral drugs due to HIV genomes integrating into CD4+ T-cells.  Researchers from Temple University and Case Western Reserve University have reported using CRISPR/Cas9 gene editing technology to remove the entire HIV genome from infected T-cells ex vivo.  Importantly, no significant off-target effects were found, providing evidence that this technique may be clinically viable in the future.

Nucleosomes obstruct Cas9 activity both in vivo and in vitro

Horlbeck et al, eLIFE (2016), 10.7554/eLife.12677, http://www.ncbi.nlm.nih.gov/pubmed/26987018

While research has focused on decreasing off-target effects, little work has been done on analyzing Cas9’s activity in different parts of the genome.  In order to understand how nucleosomes affect Cas9’s ability to access genomic DNA Horlbeck et al. performed a large scale genomic screen targeting areas both with and without nucleosomes.  This screen found low levels of Cas9 activity in nucleosome enriched regions with chromatin remodeling restoring Cas9 activity in these regions.  This research will allow CRISPR/Cas9 users to better predict guide activity in vivo.

HIV adapts to CRISPR/Cas9 inactivation

Wang et al (2016) Cell Reports http://www.cell.com/cell-reports/abstract/S2211-1247(16)30298-4

On April 7th a Cell Reports published a study that determined CRISPR/Cas9 gene editing not only failed to inactivate HIV, but ultimately led to its ability to evade future cleavage.  Chen Liang’s group at the University of Montreal found that after CRISPR/Cas9 treatment, infected T-cells  still produced HIV particles.  After sequencing it was found that these new viral particles had small mutations near the site of CRISPR/Cas9 cleavage indicative of NHEJ repair.  Liang’s group hypothesizes that treatment with CRISPR/Cas9 failed to induce a mutation that inactivated the HIV genome while simultaneously mutating the guide RNA site preventing future CRISPR/Cas9 targeting with the same guide RNA.  Liang’s group suggests that for CRISPR/Cas9 to be an effective treatment multiple guide RNAs will be required.