[Exploration of ribosomal DNA copy number as an early biomarker for exposure to chemical carcinogens].

As the relationship between exposure to chemical carcinogens and human health risks becomes increasingly clear, identifying effective biomarkers to reveal early exposure and prevent the occurrence and development of tumors has become particularly critical. Ribosomal DNA (rDNA), a cluster of genes encoding ribosomal RNA, has emerged as a focal point in chemical carcinogen exposure research in recent years, due to its high copy number within cells and sensitivity to environmental stimuli. The dynamic changes in rDNA copy numbers, especially the significant alterations observed following exposure to environmental carcinogens, have rendered it a promising potential biomarker. This paper aims to systematically review the theoretical underpinnings and research progress of rDNA copy numbers as a biomarker for exposure to chemical carcinogens, and further discuss the challenges and prospects in future research and applications.