AKR1C2 and chronic obstructive pulmonary disease: In the former analysis, Bacteroidetes Prevotella was correlated with genes WDR72, AKR1C2 and SETDB1, and methylation sites CpG-TIMP3;SYN3, CpG-UTP11L and CpG-PHACTR2; CpG-UTP11L was in turn correlated with genes WDR72 and AKR1C2, and CpG-TIMP3; SYN3 was correlated with gene WDR72. In the COPD*HIV analysis, Bacteroidetes Prevotella was correlated with genes FASTKD3, FUZ, and ACVR1B, and CpG-FUZ and CpG-PHLDB3.