A new gene editing tool spreads in scientific community like a wildfire. CRISPR-Cas9 may change our life faster and deeper than all the information technology since 1945. CRISPR has in three years brought a revolution in medical science, agriculture, and in biotechnology.
The new precision technology of CRISPR-Cas9 makes it possible to alter the genome of any living organism. The technology applies as well to humans as on bacteria. It works precisely and has a low cost. CRISPR-Cas9 tools are already available from a webshop, and the prices start at 30 euros. The new DNA-RNA pairing technology has even created a new subculture of biohackers.
CRISPR-Cas9 is both a form of microbial immune system and a name for related gene editing technology. Within a short timeframe, in three years, it has made a revolution in life sciences and even gotten a new competitor or “cousin”. Researcher Feng Zhang’s group in Harvard has developed CRISPR-Cpf1. Potentially Cpf1 protein represents another huge leap in gene editing by offering researchers more options in targeting and cleaving the DNA.
CRISPR-Cas tools make it possible for the first time in history to modify genes in living organisms very precisely and at a very low cost. The technological leap can be compared to the cost benefit when companies moved from mainframes to microprocessor based computing in the early 1980s. In semiconductor terms, the revolution is analogous to leap from vacuum tubes to transistors during the 1950s. The use of CRISPR tools makes it possible to cure hereditary diseases, create new crop plants in months and program a yeast to produce precursors for biofuels. Those are just some examples of gene editing projects under progress in different laboratories.
The spread of CRISPR-Cas9 tools has been extremely fast when we speak about implementation of basic scientific research for clinical use. This, arguably the most significant genetic tool of this century was invented just some four years ago in 2012.
In 2012 French-born Emmanuelle Charpentier, 48, then working at the Umeå University in Sweden, and an American Jennifer Doudna, 52, at UC Berkeley were both making research on the CRISPR-Cas9 immune system in Streptococcus pyogenes bacteria. It was transatlantic cooperation between Californian and Swedish laboratories in the best sense.
The seeds of the gene editing revolution were sowed a year earlier in 2011 when Charpentier and Doudna attended a microbiology conference in San Juan, Puerto Rico. They walked in old San Juan and started to talk about their common interest, bacterial immune systems. Discussions led to cooperation between two laboratories. A breakthrough came in 2012 when they were able to re-engineer Cas9 enzyme and use it as a general DNA programming tool.
With the help of RNA Cas9 could be reprogrammed to cut bacterial DNA in selected points. After cutting the double helix DNA, it was possible to bring a new gene, a DNA sequence, to the cutting point and then repair double strand DNA lesions. Previously scientists edited genes by modifying specific protein sequences to change DNA. To achieve this complicated techniques were used like Zink compounds or even radiation.
Most often those methods were imprecise, slow and expensive “hardware” wired changes in the genome. CRISPR-Cas9 brought “software programming” to gene technology.
The mechanism is principally same which allows bacteria to defend itself. Its immune system works by copying and cutting virus DNA when a virus attacks the bacteria. The cutting and copying process happens in certain repeating gene sequences in bacterial double helix DNA. Those prokaryotic cells like Streptococcus pyogenes bacteria lack a membrane-bound nucleus but have clustered regularly interspaced short palindromic repeats, CRISPRs in their DNA structure.
“Not only were we able to work out how it (CRISPR-Cas9) worked, we were able to reprogramme it to recognize new DNA sequences,” stated Jennifer Doudna in an interview in Independent newspaper in 2013.
The gene editing works with most living organisms
The second major implication was that the same genome editing technology applies to all living organisms. It is possible to remove individual genes from DNA, but it is also possible also bring new genes to the cell or genome. Those it came possible to remove genes that caused hereditary diseases, as well as to bring new properties to the plant or animal. Those gene controlled properties can be almost anything from stronger muscles in animals to greater intelligence in humans or more salt resistance in tomatoes.
CRISPR-Cas9 was an acronym that almost nobody had heard anything in the scientific community before 2012. The tipping point came after Doudna and Charpentier’s published their research that year in Science. The article started a worldwide race to implement CRISPR-Cas9 to “myriad” biotechnological challenges. They made almost an understatement in their research result conclusions. A citation from the article:
“We propose an alternative methodology based on RNA-programmed Cas9 that could offer considerable potential for gene-targeting and genome-editing applications.” (1)
It was a modest conclusion statement when we today look what results and new research that discovery generated.
Patent disputes and a lot of venture capital
Gene technology has made enormous progress during the last 30 years. Yoshizumi Ishino found CRISP repeats in 1987 at Osaka University. It was unclear, what functions CRISP had in the bacterium.
The technological CRISPR breakthrough in 2012 has generated besides worldwide cooperation also heated patent disputes between research institutes. Charpentier and Doudna were first to publish their invention in Science. They also had some luck in timing when publishing their research. Science magazine published Charpentier and Doudna's article in August 2012. A research group led by Virginijus Siksnys at the Vilnius University in Lithuania sent the first paper of CRISPR-Cas9 copy and cut mechanism to Proceedings of the National Academy of Sciences a month earlier, but the magazine published it only later in September 2012.
Very rapidly scientific community proved that CRISPR-Cas9 could also be used in complex eukaryotic animal cells to edit the genome. In late 2012 and early 2013, Feng Zhang’s and George Church’s groups at Harvard described how CRISPR-Cas9 could be used to modify human cell cultures.
Today there are available tens of thousands guide RNA in various libraries. By using RNA from those collections, scientists have already edited a very wide range of complex organisms from fruit flies to monkeys and even human embryos. The innovation has spread worldwide to public and private research laboratories. New scientific articles on the subject appear weekly in a rapid stream in major science publications. Recent publications like Nature, Science, Scientific American and New Scientist have pages full of new CRISPR research and patent reports.
Frankenstein issues in the air
CRISPR-Cas9 bring not just tremendous opportunities but also immense risks at a level that is comparable to the effects of nuclear technology. The ethical use of biotechnology is more important than ever before. It is possible to implement new genetic features and even to create new plants and animal species rapidly and reasonably cheaply. The new species like new kind of disease-carrying mosquitoes may become a larger risk for humanity than nuclear weapons.
Biological weapons are not a new invention, but it has never before been so easy to create new organisms and use them as a weapon of mass destruction, WMD. Those modified organisms can be used directly against different species like humans or indirectly to destroy crops or whole ecosystems worldwide.
James Clapper, US director of national intelligence, warned in February 2016 in the US Senate first time of risks, which genome editing tools like CRISPR-Cas9 may bring. More information about the statement is in this public document.
Both CRISPR-Cas9 inventors Jennifer Doudna and Emmanuel Charpentier have also in various interviews spoken about the ethical issues the innovation has brought up. Discussion about embryo engineering, eugenics and germline gene therapy are just some of those important questions.
On the positive side, we will see probably a multitude of more constructive fruits of CRISPR-technology. Medical companies develop new more efficient medicines and produce them with lower costs. The medical community is testing different immune cell modifications based on CRISPR-Cas9 technology to fight cancer.
The costs of genome editing have during the recent years come radically lower like the prices in computing. CRISPR-Cas9 is one pivotal part of that trend. It is here now, available for anybody, toolkits costing under 100 euros, or even less. Instructions for its use are downloadable from the Internet.
By making DNA editing radically easier than ever before many new materials and cheap manufacturing methods come possible. Thanks to CRISPR the world will in best case see more healthy people, more and better food and many pressing ecological problems solved.
CRISPR-Cas9 is a rapid tool, but we must be patient. CRISPR-Cas9 means a revolution in life sciences, but it is just one tool in molecular biology. Other essential tools are also needed when scientists edit genes, things like DNA sequencing and analyzing systems and PCR, the Polymerase Chain Reaction, technology. This fact and many safety issues involved slow advances when medical industry applies CRISPR-Cas9 techniques in its development projects. New drug development is still time-consuming.
The delivery challenges of new genetically manipulated cells or medicines may also be demanding as generally in gene transfer. Researchers need to find efficient ways to carry a working CRISPR into specific tissues.
The promise of CRISPR-Cas9 is real. It is not a wild guess that this technology may change our living conditions completely within ten to twenty years. CRISPR may finally realize the promise of synthetic biology. We may solve plenty of previously unsolvable problems in food and energy production, in medicine and materials science.