PADI4 and rheumatoid arthritis: In rheumatoid arthritis (RA), the GTG haplotype [SNPs 89G/A (rs11203366), 90T/C (rs11203367), and 92G/C (rs874881)] of the PADI4 gene confers susceptibility for presenting the disease, and higher levels of PADI4 mRNA [[22], [23], [24], [25]].