In genetics, an insertion is the addition of one or more nucleotide base pairs into a DNA sequence. This can often happen in microsatellite regions due to the DNA polymerase slipping. Insertions can be anywhere in size from one base pair incorrectly inserted into a DNA sequence to a section of one chromosome inserted into another. The mechanism of the smallest single base insertion mutations is believed to be through base-pair separation between the template and primer strands followed by non-neighbor base stacking, which can occur locally within the DNA polymerase active site. On a chromosome level, an insertion refers to the insertion of a larger sequence into a chromosome. This can happen due to unequal crossover during meiosis.
CRISPR is a family of DNA sequences found in the genomes of prokaryotic organisms such as bacteria and archaea. These sequences are derived from DNA fragments of bacteriophages that had previously infected the prokaryote. They are used to detect and destroy DNA from similar bacteriophages during subsequent infections. Hence these sequences play a key role in the antiviral defense system of prokaryotes and provide a form of acquired immunity. CRISPR is found in approximately 50% of sequenced bacterial genomes and nearly 90% of sequenced archaea.
Jennifer Anne Doudna is an American biochemist who has done pioneering work in CRISPR gene editing, and made other fundamental contributions in biochemistry and genetics. Doudna was one of the first women to share a Nobel in the sciences. She received the 2020 Nobel Prize in Chemistry, with Emmanuelle Charpentier, "for the development of a method for genome editing." She is the Li Ka Shing Chancellor's Chair Professor in the department of chemistry and the department of molecular and cell biology at the University of California, Berkeley. She has been an investigator with the Howard Hughes Medical Institute since 1997.
Cas9 is a 160 kilodalton protein which plays a vital role in the immunological defense of certain bacteria against DNA viruses and plasmids, and is heavily utilized in genetic engineering applications. Its main function is to cut DNA and thereby alter a cell's genome. The CRISPR-Cas9 genome editing technique was a significant contributor to the Nobel Prize in Chemistry in 2020 being awarded to Emmanuelle Charpentier and Jennifer Doudna.
Feng Zhang is a Chinese-American biochemist. Zhang currently holds the James and Patricia Poitras Professorship in Neuroscience at the McGovern Institute for Brain Research and in the departments of Brain and Cognitive Sciences and Biological Engineering at the Massachusetts Institute of Technology. He also has appointments with the Broad Institute of MIT and Harvard. He is most well known for his central role in the development of optogenetics and CRISPR technologies.
CRISPR interference (CRISPRi) is a genetic perturbation technique that allows for sequence-specific repression of gene expression in prokaryotic and eukaryotic cells. It was first developed by Stanley Qi and colleagues in the laboratories of Wendell Lim, Adam Arkin, Jonathan Weissman, and Jennifer Doudna. Sequence-specific activation of gene expression refers to CRISPR activation (CRISPRa).
A protospacer adjacent motif (PAM) is a 2–6-base pair DNA sequence immediately following the DNA sequence targeted by the Cas9 nuclease in the CRISPR bacterial adaptive immune system. The PAM is a component of the invading virus or plasmid, but is not found in the bacterial host genome and hence is not a component of the bacterial CRISPR locus. Cas9 will not successfully bind to or cleave the target DNA sequence if it is not followed by the PAM sequence. PAM is an essential targeting component which distinguishes bacterial self from non-self DNA, thereby preventing the CRISPR locus from being targeted and destroyed by the CRISPR-associated nuclease.
Emmanuelle Marie Charpentier is a French professor and researcher in microbiology, genetics, and biochemistry. As of 2015, she has been a director at the Max Planck Institute for Infection Biology in Berlin. In 2018, she founded an independent research institute, the Max Planck Unit for the Science of Pathogens. In 2020, Charpentier and American biochemist Jennifer Doudna of the University of California, Berkeley, were awarded the Nobel Prize in Chemistry "for the development of a method for genome editing". This was the first science Nobel Prize ever won by two women only.
Editas Medicine, Inc.,, is a clinical-stage biotechnology company which is developing therapies for rare diseases based on CRISPR gene editing technology. Editas headquarters is located in Cambridge, Massachusetts and has facilities in Boulder, Colorado.
J. Keith Joung is an American pathologist and molecular biologist who holds the Robert B. Colvin Endowed Chair in Pathology at Massachusetts General Hospital and is Professor of Pathology at Harvard Medical School. He is a leading figure in the field of genome editing and has pioneered the development of designer nucleases and sensitive off-target detection methods.
Rodolphe Barrangou is the Todd R. Klaenhammer Distinguished Professor in Probiotics Research in the Department of Food, Bioprocessing and Nutrition Sciences at North Carolina State University; Co-Founder and Chief Executive Officer of CRISPR Biotechnologies; Co-Founder and Chief Scientific Officer of Ancilia Biosciences; Co-Founder, President and Chief Scientific Officer of TreeCo; and Co-Founder and member of the Scientific Advisory Board of Intellia Therapeutics. His research focuses on CRISPR-Cas9 in bacteria.
Intellia Therapeutics is a clinical-stage biotechnology company focused on developing novel, potentially curative therapeutics leveraging CRISPR-based technologies. The company’s in vivo programs use intravenously administered CRISPR as the therapy, in which the company's proprietary delivery technology enables highly precise editing of disease-causing genes directly within specific target tissues. Intellia’s ex vivo programs use CRISPR to create the therapy by using engineered human cells to treat cancer and autoimmune diseases.
Lei "Stanley" Qi is an associate professor in the department of bioengineering, and the department of chemical and systems biology at Stanford University. Qi led the development of the first catalytically dead Cas9 lacking endonuclease activity (dCas9), which is the basis for CRISPR interference (CRISPRi). His laboratory subsequently developed CRISPR-Genome Organization (CRISPR-GO).
CRISPR gene editing is a genetic engineering technique in molecular biology by which the genomes of living organisms may be modified. It is based on a simplified version of the bacterial CRISPR-Cas9 antiviral defense system. By delivering the Cas9 nuclease complexed with a synthetic guide RNA (gRNA) into a cell, the cell's genome can be cut at a desired location, allowing existing genes to be removed and/or new ones added in vivo.
Janice Chen is co-founder and chief technology officer of Mammoth Biosciences, a Brisbane, California-based company founded in 2018 that is developing diagnostic tests using CRISPR. She received her B.S. degree from Johns Hopkins University and as a graduate student at the University of California, Berkeley, she worked in the lab of CRISPR pioneer Jennifer Doudna, receiving her PhD in Molecular and Cell Biology.
Locus Biosciences is a clinical-stage pharmaceutical company, founded in 2015 and based in Research Triangle Park, North Carolina. Locus develops phage therapies based on CRISPR–Cas3 gene editing technology, as opposed to the more commonly used CRISPR-Cas9, delivered by engineered bacteriophages. The intended therapeutic targets are antibiotic-resistant bacterial infections.
CRISPR Therapeutics AG is a Swiss–American biotechnology company headquartered in Zug, Switzerland. It was one of the first companies formed to utilize the CRISPR gene editing platform to develop medicines for the treatment of various rare and common diseases. The company has approximately 500 employees and has offices in Zug, Switzerland, Boston, Massachusetts, San Francisco, California and London, United Kingdom. Its manufacturing facility in Framingham, Massachusetts won the Facilities of the Year Award (FOYA) award in 2022. The company’s lead program, Exagamglogene autotemcel, or exa-cel, has been submitted for regulatory approval in 2023.
Flagship Pioneering is an American life sciences venture capital company based in Cambridge, Massachusetts that invests in biotechnology, life sciences, health and sustainability companies. Portfolio companies include Moderna, Indigo Agriculture, Inari Agriculture and Novomer. The firm both funds and incubates companies.
Sherlock Biosciences is a biotechnology company based in Cambridge, Massachusetts developing diagnostic tests using CRISPR-Cas13. The company was founded in 2019 by Feng Zhang, Jim Collins, Omar Abudayyeh, and Jonathan Gootenberg of the Broad Institute.
