GSTM1 and chronic kidney disease: Having in mind that in chronic kidney disease the GSTM1 is normally up-regulated in a protective response to increased oxidative stress, as well as that the GSTM1 could be a surrogate for unmeasured oxidative stress markers [17,23], it seems reasonable to assume that this genetic variant may be deleterious in terms of carotid atherosclerosis and consequent stroke in ESRD patients.