Dataset of Global Methylation on Night-Shift Work and Breast Cancer

This dataset includes quantitative measurements of global DNA methylation, expressed as the mean percentage ratio of methylated sites (5-methyl-deoxy-cytidine) to total deoxyguanosine content, along with corresponding standard deviations and coefficients of variation. It also contains measurements of 8-oxo-2′-deoxyguanosine (8-oxo-dG) as a marker of oxidative DNA damage. Genomic DNA was extracted from whole blood samples collected at two recruitment centers (Bologna and Messina). All samples were analyzed in triplicate using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). Night shift work (NSW) exposure was defined as the number of night shifts worked in the previous six months. Exposure variables were categorized into three levels: non-recent exposure, intermediate exposure, and recent exposure.