IDS and chronic obstructive pulmonary disease: When only COPD subjects were examined, Sv1 still correlated with ARSB, GALNS and IDS. Interestingly, only ARSB and IDS correlated with Sv2 and none of the sulfatases correlated with Sv3. When taking into account the total expression of SUMF1 (including all splice variants) there was only a correlation with GNS in COPD patients.