Scientists are exploring gene editing as a way to correct trisomy at the cellular level. Using CRISPR-Cas9, researchers successfully removed extra copies of chromosome 21 in Down syndrome cell lines, restoring normal gene expression.
This breakthrough suggests that, with further development, similar approaches could be applied to neurons and glial cells, offering a potential treatment for those with the condition.
Gene Editing for Trisomy Treatment
Scientists are exploring gene editing as a potential way to treat trisomy at the cellular level, according to a proof-of-concept study conducted in lab-grown cells. Down syndrome occurs when a person has an extra copy of chromosome 21, affecting about 1 in 700 live births. While the condition is easily diagnosed early in development, no treatments currently exist.
In this study, Ryotaro Hashizume and colleagues used the CRISPR-Cas9 gene editing system to remove the extra chromosome from trisomy 21 cell lines. These cells were derived from both pluripotent stem cells and skin fibroblasts. The technique was able to identify and precisely target the duplicated chromosome, ensuring that after removal, each cell retained one copy from each parent rather than two identical copies.
By suppressing the cell’s natural DNA repair mechanisms, researchers increased the efficiency of removing the extra chromosome. Their findings showed that this process restored normal gene expression and cellular function in edited cells.
Potential for Future Medical Interventions
Although promising, the method is not yet ready for use in living organisms, as it can also alter the remaining chromosomes. However, researchers believe that similar approaches could eventually be applied to neurons and glial cells, paving the way for potential future treatments for people with Down syndrome.
Reference: “Trisomic rescue via allele-specific multiple chromosome cleavage using CRISPR-Cas9 in trisomy 21 cells” by Ryotaro Hashizume, Sachiko Wakita, Hirofumi Sawada, Shin-ichiro Takebayashi, Yasuji Kitabatake, Yoshitaka Miyagawa, Yoshifumi S Hirokawa, Hiroshi Imai and Hiroki Kurahashi, 18 February 2025, PNAS Nexus.
DOI: 10.1093/pnasnexus/pgaf022
