Further analysis revealed that the enrichment of H3K18la at the promoter of an m6A reader YTH N6-methyladenosine RNA binding protein 2 (YTHDF2) promoted the expression of YTHDF2 and further impaired mRNA stability of period circadian regulator 1 (PER1) and tumor protein p53 (TP53), leading to an aggressive proliferation and migration of ocular melanoma cells. This evidence concerns the gene PER1 and ocular melanoma.