Researchers at Penn State University have engineered a mushroom that doesn't brown using CRISPR/Cas9, a straightforward, inexpensive and effective technique that can be used to alter the DNA of almost any organism in which it's been tried. This mushroom is just the first in what will be a long list of genetic modifications in organisms (both food and humans) created using this technology.
Don’t you hate it when you buy a bag of mushrooms at the store and by the next day, the whole bag has turned brown and needs to be thrown out? Well, now there is a way to prevent that frustration and food waste.
A group at Pennsylvania State University has engineered a mushroom that does not brown using the genetic altering mechanism known as CRISPR/Cas9, and those researchers are preparing to get it into a grocery store near you.
The difference between this CRISPR mushroom and your “garden-variety” GMO is in how its genome was altered. Traditional GMOs contain DNA from another source, called a "transgene" that gives them their new traits (ie. bug or herbicide resistance). CRISPR editing modifies the original DNA to create a new trait (ie. non-browning) without leaving any foreign DNA behind in the genome.
It is this difference that lies at the heart of the USDA’s decision to not regulate this non-browning mushroom, as described in a letter from the Animal and Plant Health Inspection Service (APHIS), the branch of the USDA involved in this type of regulation. They go on to say that if any mushrooms do, in the future, contain inserted genetic material, those would be subject to regulation.
This non-browning mushroom has placed the USDA in the center of a scientific landslide that is both in its infancy and, at the same time, advancing at an incredibly fast pace. CRISPR is not your average scientific discovery story. Usually, scientific progress evolves painstakingly slowly, over decades, through incremental discoveries coming from multiple scientific labs in different areas of the world. It can take many years (and some amount of good luck) just to get a single paper published. Once the science is more or less settled, it is sometimes modified into a technique that can be used for clinical uses (which can take another decade).
The understanding of the CRISPR system started in 1987, when repeating DNA sequences were discovered in bacteria. With the technology available at that time, it took 20 years to work out the rest of the system — an unremarkable amount of time to figure out a complicated biological process. It was this early work that laid the foundation for the CRISPR explosion that we are in the middle of today. Figuring out the nuts and bolts of the system in bacteria in the 1990s and 2000s has allowed for scientists to build upon those basics and turn the CRISPR system into a robust genome editing tool.
CRISPR, as a tool, started to take off in 2012, when papers that introduced the technology were first published. What came out of this work was an incredibly straightforward, inexpensive and effective tool that made it possible to alter the DNA of almost any organism.
In four years — the blink of an eye in the scientific world — CRISPR has become universally accepted. It is now hard to find anyone doing genetic research who is not using the technique. In fact, CRISPR is so easy to do and so fast to implement, once you determine which gene you would like to target, you can go from start to finish in the span of a week or two. For example, CRISPR would allow for quick manipulation of the BRCA1/BRCA2 genes, two genes that are known to be associated with an increased risk of having breast cancer.
And, scientists are not just modifying food using CRISPR. Human diseases are being rapidly targeted using this same technology. In fact, there are two companies (CRISPR Therapeutics and Editas), both located in Cambridge, MA, that aim to start performing CRISPR in human cells by next year. Both of these companies have multimillion dollar investors and have very little standing in their way of moving the field at a frenzied pace out of the lab and into clinical settings. Their goal is to cure human diseases by using CRISPR to alter the changes in genes that are responsible for human diseases.
Molecular biologists predict that multiple, varied CRISPR modified foods will be in our kitchens within the year. And, without unnecessary regulation by the USDA, the pace of new foods being created will occur at lightning speed. Not only will CRISPR foods quickly take over GMOs, but, they may do so while also giving people less to get upset about.