Furthermore, the results of SLCO2A1 RNA expression and protein expression analysis (Figure 8), as well as the measurement of urinary PG metabolites, correlated with the degree of DNA methylation, suggesting that DNA methylation may be involved in the onset of IBD in these sisters, and that this epigenetic change may be involved in the recent increase in IBD patients. The gene discussed is SLCO2A1; the disease is inflammatory bowel disease.