里程碑突破：首款个性化碱基编辑疗法，成功治疗罕见遗传病，整个开发过程仅6个月

Core Viewpoint - A significant medical breakthrough has been achieved by the research team from the Children's Hospital of Philadelphia and the University of Pennsylvania, marking the first instance of a patient-specific gene editing therapy successfully treating a child with a rare and fatal genetic disease [1][4]. Group 1: Medical Breakthrough - The research titled "Patient-Specific In Vivo Gene Editing to Treat a Rare Genetic Disease" was published in the New England Journal of Medicine on May 15, 2025, detailing the development and treatment process of a customized in vivo base editing therapy [1]. - This success may pave the way for gene editing technology to be applied in treating rare diseases that currently lack medical solutions [1]. Group 2: Patient Case Study - The patient, KJ, was diagnosed with Carbamoyl Phosphate Synthetase 1 (CPS1) deficiency shortly after birth, a rare and severe genetic disorder with an incidence rate of 1 in 1.3 million among newborns [4]. - CPS1 deficiency leads to a toxic accumulation of ammonia in the body due to the lack of necessary enzymes for converting ammonia into urea, resulting in a high early mortality rate of 50% among affected infants [6]. Group 3: Gene Editing Technology - The FDA recently approved the CRISPR-Cas9 based gene editing therapy, Casgevy, for treating two relatively common genetic diseases, sickle cell disease and beta-thalassemia, marking the first FDA-approved gene editing therapy based on CRISPR technology [6]. - Base editing, developed by Professor David Liu, is a next-generation gene editing technology that does not rely on DNA double-strand breaks and can precisely repair pathogenic mutations in the human genome [6]. Group 4: Development Process - The research team quickly identified KJ's specific genetic mutations and initiated the development of a customized base editing therapy, which involved collaboration between academia and industry [7]. - The entire process of development, validation, production, and regulatory approval took only six months, during which KJ was under medical supervision and followed a strict low-protein diet [7]. Group 5: Treatment Outcomes - KJ received the experimental base editing therapy in February 2025, followed by additional doses in March and April, with no severe side effects reported [9]. - Post-treatment, KJ showed significant improvements, including the ability to tolerate more protein intake, a reduction in the required dosage of nitrogen-excreting medication, and recovery from common childhood illnesses without elevated ammonia levels [9]. Group 6: Future Implications - The research team expressed optimism about the initial results and hopes that other patients may experience similar benefits, encouraging further research into rare diseases using this method [10]. - The promise of gene therapy, long anticipated, is now becoming a reality, potentially transforming the approach to medicine [10].