Buzz
The DNA-editing tool known as CRISPR frequently appears in news headlines due to its role in numerous medical advancements. While it has the theoretical ability to locate, remove, and replace problematic DNA sections with new nucleotides, the process is often more complex in practice.
Originally a bacterial defense mechanism, CRISPR was adapted by scientists for biotechnological use. Bacteria possess DNA segments with unique repetitive patterns, known as "clustered regularly interspaced short palindromic repeats," which serve as a record of past viral encounters. Proteins such as Cas9 ("CRISPR associated [protein] 9") use this data to identify and eliminate returning threats, guided by specific DNA sequences.
In laboratory settings, researchers can modify this system to target specific DNA sequences, including those within human genes. This opens up possibilities like correcting faulty genes in individuals with genetic disorders, highlighting CRISPR's immense potential.
However, CRISPR is still an emerging technology with limitations. Scientists are addressing challenges such as ensuring safety for human use and delivering CRISPR molecules effectively to target cells. While promising, it’s important to maintain realistic expectations about its current capabilities.
Criminals are not utilizing it to avoid DNA detection
While criminals can be identified through DNA databases, the idea that a murderer could alter their DNA to evade detection is far-fetched. (The Daily Mail mentioned a scientist’s speculation about this possibility.) However, CRISPR faces significant hurdles, such as delivering the DNA-editing tool to every targeted cell. Currently, it’s unclear whether CRISPR can modify every cell in a human body.
Conclusion: This scenario is unlikely to occur in the near future.
Enhancing your muscles with CRISPR is also improbable
What if you only want to modify a small part of your DNA for aesthetic reasons? Biohacker Josiah Zayner attempted this by injecting a CRISPR-based solution into his arm to inhibit the myostatin gene. While babies born with a natural defect in this gene develop muscular physiques due to unrestricted muscle growth, achieving similar results in adults through gene editing is not guaranteed.
Even after researchers conducted a myostatin-blocking CRISPR experiment on 35 dog embryos, only two puppies were born with the intended mutation. However, these two did not develop the expected muscular appearance.
Conclusion: highly improbable.
Potential for disease treatment exists
While CRISPR faces significant hurdles in adult humans, clinical trials are set to begin this year. Researchers in Europe and the US aim to address blood disorders like beta-thalassemia and sickle-cell disease. The process involves extracting patients’ blood stem cells, using CRISPR to correct genetic defects, and reintroducing the modified cells into their bodies. This approach is akin to a bone marrow transplant, but the patient serves as their own donor.
Conclusion: promising, but its success remains uncertain.
CRISPR-modified crops might become the next generation of GMOs
Many of today’s crops differ significantly from their wild ancestors. Some changes resulted from natural mutations thousands of years ago, while others were shaped by selective breeding. In recent years, scientists have gained the ability to directly alter the DNA of living organisms.
These methods are often referred to as genetic engineering, and the resulting plants are labeled as GMOs, or genetically modified organisms. (Contrary to some negative perceptions, GMOs are neither inherently better nor worse for health than non-GMO alternatives.)
GMO crops face stricter government regulations compared to traditionally bred plants. However, the USDA recently ruled that CRISPR-edited crops will not be classified as GMOs if they lack foreign DNA. For instance, adding a gene from another organism to corn would classify it as a GMO, but using CRISPR to remove a gene without introducing new DNA is treated the same as conventional breeding.
Meanwhile, the FDA has stated that CRISPR applications in animals are considered a form of gene therapy, requiring regulation as veterinary drugs. This means creating a hornless cow or a purebred dog free from harmful inbreeding mutations would involve an expensive drug approval process.
Conclusion: CRISPR-modified plants may soon appear in local grocery stores, while CRISPR-edited animals encounter greater regulatory and practical challenges.
