Our understanding of the human genome has continued to increase since it was first accurately sequenced in 2003. Building on that success, biotechnology is advancing to the point where it’s viable to alter the DNA encoded within a cell. This process is known as gene editing. Understandably, gene editing has creepy connotations for some, but it could deliver some drastic leaps forward in the fight against disease, as well as delivering other benefits, like ensuring we have enough food to feed the planet.
Here are seven things you need to know about gene editing:
1. Gene editing can be used to “fix” harmful genes
Gene editing can have particular advantages when “bad” genes are detected – genes that could endanger the health of the organism (be it a human, animal, or plant) or its descendants. These harmful characteristics can, in theory, be altered. In humans, this could ensure children do not suffer the same inherited diseases as their parents, or mutations could be fixed before they result in disease. In animals, common problems associated with certain breeds, such as breathing problems or susceptibility to blindness, could be eliminated. And in plants, crops can be developed that are resistant to pests and disease.
2. CRISPR (pronounced “crisper”) is the method to watch
There’s one particular method of gene editing that is showing enormous potential. CRISPR, which was first developed in 2012 at the University of California, Berkeley, was adapted from a naturally occurring gene-editing system in bacteria. Given that the human body contains around 37 trillion cells, the microscopic scale involved in gene editing is truly amazing. The nucleus, where most DNA resides, takes up around 10 percent of the mass of a typical cell, so the level of accuracy needed to cut something that tiny is almost inconceivable. At present, CRISPR is the simplest and most precise way of identifying where a DNA strand needs to be cut and then splitting the strand.
3. Gene editing could transform healthcare
Much of the work being done with gene editing is in the field of healthcare, with some of the most exciting projects focusing on the “correction” of DNA mutations that can lead to serious illnesses. In one example, gene editing has been shown to fix the mutation responsible for Duchenne Muscular Dystrophy – a devastating condition that affects one in 3,500 young boys and results in early death. Gene editing for Duchenne Muscular Dystrophy has been trialed on beagle dogs, and the hope is it will lead to a viable treatment for humans.
4. Gene editing could solve the problem of food allergies
Gene editing could also potentially eliminate the dangers caused by allergens. That’s because the compounds and substances within foodstuffs such as cereals, dairy products, and nuts that are responsible for allergic reactions can potentially be eliminated through gene editing. In one project, researchers at Wageningen University in the Netherlands are removing antigens in gluten from wheat, making it digestible for those with a gluten intolerance.
5. There are two main types of gene editing
Gene editing work carried out to prevent disease or improve health can be classified into two types. The first is germline therapy, which can cause changes in reproductive cells (eggs and sperm) and therefore cause changes that will be inherited by offspring. The second is somatic, which targets non-reproductive cells and can potentially cure or slow down the spread of disease in the target organism.
6. Many countries do not allow gene editing
Germline editing in humans is currently banned in many countries, including much of Europe, as its long-term results are not understood. This will possibly change in the coming years as a public discussion on the ethics and implications advances, or the need for eradicating disease becomes more urgent. Interestingly, germline editing isn’t banned in China or the US.
7. Gene editing could boost plant health, too
As well as human health, plant health can also be improved with gene editing. We all know that vegetable and cereal crops are susceptible to pests and diseases. By editing plant genomes, their resistance to these threats can be increased, leading to higher yields and less dependence on harmful chemical interventions. For example, researchers at Penn State University are working on creating genetically enhanced cacao trees that will be resistant to the disease and fungus that destroys up to 30 percent of the worldwide cacao crop before their pods can be harvested. This is done by suppressing a gene that decreases the plant’s ability to fight off infections. As well as increasing the global supply of cacao (great news for chocoholics), this could also hugely improve the livelihoods of cacao farmers, who are some of the most deprived agricultural workers. At present, the cultivation of genetically modified crops is banned in some countries, including the UK. However, many countries do permit the cultivation of crops created by gene editing, with varying degrees of regulation. These countries include Canada, China, the US, Australia, and Brazil.