The expression of GRIK2 strongly correlated with methylation of all three GRIK2 CpGs determined as DVPs in COPD (cg24753760, Fig. 6c; cg06247406, Fig. 6d; cg16009558, Fig. 6e), highly suggestive of aberrant GRIK2 CpG methylation leading to increased GRIK2 expression in COPD parenchymal fibroblasts. The gene discussed is GRIK2; the disease is chronic obstructive pulmonary disease.