m6A is the most prevalent internal modification in eukaryotic mRNA and preferentially occurs at the consensus sequence [G/A/U][G>A]m6AC[U>A>C] with a non-stoichiometric ratio.Although it was first found in 1970s,relative to DNA modifications,the research on m6A lagged behind due to the lack of detection techniques for RNA modifications.Until 2011,the discovery of FTO as an m6A-demethylase demonstrates m6A is a reversible and dynamic RNA modification and reignites investigation of m6A.