Japanese scientists led by Dr. Ryotaro Hashizume at Mie University have successfully used CRISPR-Cas9 gene editing to remove the extra chromosome 21 responsible for Down syndrome in lab-grown human stem and skin cells. This marks the first instance of CRISPR deleting a full chromosome via allele-specific editing. Eliminating the extra chromosome normalized cell behavior, increasing growth rates and correcting gene expression patterns. While this breakthrough opens avenues for therapeutic research, ethical concerns about potential clinical application remain amidst ongoing debates.