Japanese Scientists Remove Extra Chromosome Causing Down Syndrome With CRISPR

In a groundbreaking scientific breakthrough, Japanese researchers have successfully removed the extra chromosome responsible for Down syndrome in human cells using CRISPR gene-editing technology. This world-first achievement marks a major step toward developing therapies that directly target the genetic root of the condition.

Led by Dr. Ryotaro Hashizume, the team developed a technique called “trisomic rescue,” which uses highly specific CRISPR guides to locate and delete the third copy of chromosome 21. This is the genetic abnormality that causes Down syndrome, a condition that affects cognitive development and overall health due to the presence of an extra chromosome.

What makes this technique extraordinary is its precision. The method targets only the extra chromosome, leaving the two healthy copies intact. The researchers achieved a success rate of over 30% by temporarily suppressing the cell’s DNA repair mechanisms to enhance editing efficiency.

After the removal of the extra chromosome, the edited cells showed normalized gene activity, improved cell growth, and better stress response. The breakthrough was observed in both stem cells and adult skin cells, offering hope that it could be applied to different types of tissues in the future.

This discovery is the first time CRISPR technology has been used to eliminate an entire chromosome from human cells. It goes beyond editing a single gene and ventures into the territory of complete chromosome deletion, opening up new possibilities in genetic medicine.

While this research is still in the laboratory phase and has not yet been tested in living organisms, it lays the foundation for future therapies that could dramatically change how genetic disorders like Down syndrome are treated. Scientists are now working on applying the technique to brain cells to explore whether it could improve neurological development and cognitive outcomes.

However, the breakthrough also raises ethical questions. Advocates stress the importance of ensuring that such advancements do not lead to discrimination against individuals with Down syndrome or a rise in genetic “perfectionism.” Any future clinical applications will need to be developed with caution, inclusivity, and deep ethical consideration.

Still, the scientific community views this as a monumental advancement. The ability to remove an entire chromosome and restore cell function offers a glimpse into a future where gene therapy doesn’t just manage symptoms but rewrites the root cause of genetic conditions.