Molecular epidemiology is a branch of epidemiology that focuses on the use of molecular biology techniques to study the distribution and determinants of disease within populations. This field combines traditional epidemiological methods with molecular biology tools to investigate the genetic and environmental factors that contribute to the development and spread of diseases. Researchers in molecular epidemiology use techniques such as DNA sequencing, genotyping, and gene expression analysis to identify biomarkers, genetic risk factors, and pathways involved in disease development. By understanding the molecular mechanisms underlying diseases, researchers can develop more targeted and personalized interventions for disease prevention and treatment.