Core Viewpoint - The article discusses the advancements in prime editing technology, particularly the development of the next-generation prime editor (vPE) that significantly reduces genomic errors compared to its predecessor, the original prime editor (PE) [3][4][5]. Group 1: Prime Editing Technology - Prime Editor (PE) is an advanced CRISPR gene editing tool developed by Professor Liu Ruqian's team in 2019, capable of editing and repairing 89% of 75,000 known pathogenic human genetic mutations [3][5]. - The editing process involves the prime editor binding to the genomic target, creating a single-strand DNA cut, and using pegRNA to guide the insertion or replacement of new DNA sequences [5][6]. - A significant challenge remains in eliminating errors produced as byproducts of prime editing, specifically insertion/deletion mutations (indels) that can lead to unpredictable and potentially harmful DNA sequences [5][6]. Group 2: Advances in Error Reduction - The research team identified key factors driving indel error formation, including the potential for the edited 3' new strand to extend beyond the pegRNA template and the conversion of single-strand cuts into double-strand breaks due to mismatch repair [6][7]. - By engineering the prime editor to induce instability in the competitive 5' strand, the team discovered a significant reduction in indel errors, leading to the development of the next-generation prime editor (vPE) [7][9]. - The vPE demonstrates a substantial improvement in editing efficiency while reducing the indel error rate to 1/60 of the original prime editor, with errors occurring only once every 543 edits [9].

Core Viewpoint - The article discusses the emerging understanding of synonymous mutations in human cells, challenging the traditional view of these mutations as neutral and highlighting their potential impact on cellular adaptability and disease [2][5][6]. Group 1: Research Background - A study by a team from the University of Michigan suggested that synonymous mutations in yeast may not be neutral and could affect cellular adaptability, reigniting interest in their biological effects [1]. - Previous research has linked a small number of synonymous mutations to human diseases, indicating their potential role as cancer drivers, but experimental confirmation remains limited [6]. Group 2: New Research Findings - A new study published by researchers from Peking University developed a high-throughput screening technology named PRESENT to investigate functional synonymous mutations in the human genome [4]. - The research utilized an advanced prime editing system (PEmax) to create a library targeting 3,644 human protein-coding genes, allowing for large-scale screening of synonymous mutations [7]. Group 3: Methodology and Tools - The study integrated single-cell screening methods with the PRESENT technology, termed DIRECTED-seq, to systematically evaluate the impact of identified synonymous mutations on gene expression [8]. - A specialized machine learning model called DS Finder was developed to analyze the effects of functional synonymous mutations on various biological processes, such as mRNA splicing and transcription [9][11]. Group 4: Key Findings - The research indicated that synonymous mutations exhibit different fitness effects compared to non-synonymous mutations, although their phenotypic distribution was similar to negative controls [9]. - The study identified that synonymous mutations could alter RNA folding and affect translation, with PLK1_S2 being a notable example, and combined screening data with predictive models to identify clinically relevant synonymous mutations [9].