Researchers from the Chinese Academy of Sciences led by Prof. Gao Caixia have developed two innovative genome editing platforms, collectively termed Programmable Chromosome Engineering (PCE) systems. These technologies enable precise DNA modifications at kilobase to megabase scales in eukaryotic cells, overcoming previous limitations of the Cre-Lox system such as reversible recombination and residual genomic scars. Integrating a high-throughput recombination site modification platform, protein engineering powered by AI-informed constraints, and a scarless editing strategy using prime editing, these methods represent a major advance in genome engineering with broad implications for basic research and crop improvement.