RUNX2 and ankylosing spondylitis: The whole-epigenome studies (EWAS) of osteoporosis have not identified the significant signatures of the differential CpG site methylation of the RUNX2 gene [28], while according to various data, the methylation status of the gene may influence the risk of ankylosing spondylitis [29], and the methylation status of the adjacent region to the RUNX2 gene may be associated with the risk of developing osteoarthritis [30].