Confirming this, Kloska et al. showed how different alleles coding for OPG and RANKL with different types of monocyte methylation have increased the serum expression in CF (the allelic variants associated with CNO are OPG 245T>G, 1181G>C and 1217C>T and RANKL 290C>T, 643C>T and 693G>C) [47]. The gene discussed is TNFSF11; the disease is cystic fibrosis.