To investigate the role of DNA methylation in development of myopia by evaluating dynamic change of DNA methylation in promoter of collagen 1A1 (COL1A1) in association with COL1A1 mRNA level in sclera following form deprivation myopia (FDM) and their recovery in mice.  Consistent with the reduced COL1A1 mRNA and development of myopia, the frequency of methylation in CpG island of COL1A1 promoter/exon 1 increased during FDM phase and returned to normal during the recovery phase. It suggests that the DNA methylation of COL1A1 promoter/exon 1 may contribute to myopic scleral collagen degradation.