In a coal worker's pneumoconiosis (CWP) model of specific-pathogen-free (SPF) male Sprague-Dawley (SD) rats and rat alveolar type II cells (RLE-6TN) established by Zhang, the protein expressions of DNMT1, DNMT3a, DNMT3b, MBD2, and MeCP2 changed compared with the control group. The gene discussed is DNMT3B; the disease is pneumoconiosis.