Dysregulation of PADI4 is involved in the occurrence and development specific human diseases, such as tumor development (Chang and Fang, 2010), multiple sclerosis (Mastronardi et al., 2006), and rheumatoid arthritis (RA) (Suzuki et al., 2003; Guzmán-Guzmán et al., 2015). This evidence concerns the gene PADI4 and rheumatoid arthritis.