4 Groundbreaking Innovations Scientists Have Achieved With CRISPR

There has been significant attention on mosquitoes, particularly genetically modified ones. In the summer of 2021, researchers from the University of California, Santa Barbara, and the University of Washington developed a technique to alter mosquito vision, making it challenging for them to locate human hosts.

This remarkable achievement was made possible using CRISPR, a cutting-edge genetic engineering tool.

"CRISPR was initially a bacterial defense mechanism against viruses," explained Raphael Ferreira, a genomics engineer at Harvard Medical School, during a 2021 interview. Often likened to "molecular scissors," CRISPR employs specialized proteins known as Cas — short for CRISPR-associated enzymes — to precisely cut DNA or RNA at predetermined locations. This allows the system to insert or remove specific genes, resulting in a gene-edited organism.

CRISPR unlocks a vast array of possibilities, particularly in human health, such as altering mosquito vision. However, its applications extend far beyond. "We now have numerous variants of this technology, enabling virtually any type of genetic engineering," Ferreira noted.

Here are some of the most extraordinary ways scientists are utilizing CRISPR, both inside and potentially outside the laboratory.

1. Cultivating Spicy Tomatoes and Decaf Coffee Beans

Picture biting into a sun-ripened tomato. What flavors do you expect? Sweetness? A hint of acidity or savoriness? What if it had a spicy kick?

An international team of geneticists suggests that the future flavor profile of tomatoes could include a spicy twist. Researchers from Brazil and Ireland are exploring CRISPR to activate dormant capsaicinoid genes in tomato plants, the same genes responsible for the heat in chili peppers. Beyond crafting the ultimate bloody Mary, these plants could provide a cost-effective alternative to traditional peppers, which are challenging to cultivate.

CRISPR could also revolutionize your morning coffee. U.K.-based Tropic Biosciences is working on a coffee bean genetically modified to grow without caffeine. This innovation is significant, as current decaffeination processes involve soaking beans in chemicals like ethyl acetate or methylene chloride (found in paint remover), which strip away both caffeine and much of the flavor. CRISPR coffee aims to deliver a smooth, flavorful cup without the caffeine.

2. Crafting Hangover-Free Wine

If you've ever dreamed of enjoying a night out without the dreaded hangover, science might have the answer. Researchers at the University of Illinois have used CRISPR to enhance the health benefits of a yeast strain used in winemaking, while also removing the genes responsible for next-day headaches.

The yeast, Saccharomyces cerevisiae, is a polyploid organism, meaning it contains multiple copies of each gene. This characteristic makes it highly adaptable but challenging to modify using traditional methods, which could only target one gene copy at a time. CRISPR, however, offers a more efficient solution.

CRISPR enables genetic engineers to target every copy of a gene simultaneously. Compared to older methods, "the complexity achievable with CRISPR is far superior," Ferreira explains. "It’s all about efficiency."

Using CRISPR, the Illinois team increased the levels of heart-healthy resveratrol in their wine while eliminating the genes responsible for hangovers.

3. Hornless Cattle

In cattle farming, horns are typically undesirable. On mature bulls, they present risks to farmers, other cattle, and sometimes the animals themselves.

Traditionally, cattle are dehorned by destroying the horn-producing cells on their foreheads, located on bony structures called horn buds. This is done using painful methods such as knives, hot irons, electricity, or caustic chemicals like sodium hydroxide. These practices can cause facial disfigurement or eye damage. CRISPR, however, offers a more humane solution.

Using CRISPR, researchers have developed a gene for hornless cattle, removing the need for painful dehorning procedures. Remarkably, some of these genetically modified bulls have passed the trait to their offspring, ensuring its presence in future generations. This breakthrough has been hailed as a major success, with geneticist Alison L. Van Eenennaam from the University of California, Davis, describing horn removal as "a significant animal welfare issue" and urging further research in a Nature essay.

Public opinion on genetically modified crops and livestock has historically been skeptical, though recent studies indicate that attitudes are shifting. But what if CRISPR were applied to something more akin to "Jurassic Park" than "Charlotte's Web"?

4. Reviving Extinct Species

One of the most ambitious applications of CRISPR is its potential to revive extinct species. Currently, there is serious discussion about bringing back the passenger pigeon.

Once, passenger pigeons filled North American forests in flocks numbering hundreds of millions, their presence so vast that they darkened the skies and created what conservationist Aldo Leopold called "a feathered tempest." However, their numbers declined sharply during the 18th and 19th centuries as European settlers expanded across the continent.

Passenger pigeons were not only abundant but also highly prized for their taste. They were hunted in large numbers by Euro-Americans for both sustenance and sport. While hunting alone might not have decimated their population, the simultaneous destruction of their nesting habitats led to a rapid decline. By the early 20th century, the species was nearly extinct. The last known passenger pigeon, named Martha, died in captivity in 1914.

Today, scientists are exploring CRISPR as a tool to revive these iconic birds. The California-based organization Revive & Restore has launched the Passenger Pigeon Project, which seeks to reintroduce the species by editing the genome of the band-tailed pigeon, a close relative. If successful, this method could potentially restore other extinct or endangered species, such as the black-footed ferret or even the woolly mammoth. While the ethical implications remain debated, CRISPR has undeniably turned science fiction into reality.