“…Recently, a rare case of BNT162b2 mRNA vaccine-associated myositis was observed in a 34-year-old woman (Magen et al 2022). DNA methylation and corresponding epigenetic alterations also disturb the efficacy of DNA and mRNA vaccines (Pang et al 2022). Noticeably, several approved nucleic acid vaccines (ZyCoV-D, DNA plasmid vaccine utilized intradermally, India), BNT162b2 (mRNA, 2 doses, Germany), mRNA-1273 (Moderna, USA, 2 doses), ARCoV (WALVAX, China) and clinical trials including 302-COVID19 (DNA plasmid vaccine, phase II/III intramuscular, Japan), INO-4800 (DNA plasmid, phase II/III, intradermal, China), GX-19N (DNA vaccine, Genexine, phase II/III), Covigenix VAX-001 (DNA vaccine, Entos Pharmaceuticals, phase I/II, intramuscular), COVID-eVax (DNA vaccine, phase I/II, intramuscular, Rome) and bacTRL-Spike (DNA vaccine, phase I, oral, Symvivo) have been developed (Sheridan 2021;Liu and Ye 2022a).…”