In the SLE patients, PON1 paraoxonase activity correlated positively with the proportion of large HDL % (r = 0.34808, P = 0.0123) and with its concentration (r = 0.33598, P = 0.0159), while it showed a negative association with the proportion of intermediate HDL (r = −0.38145, P = 0.0057). The gene discussed is PON1; the disease is systemic lupus erythematosus.