Relationships of glioma risk with genetic variation in several additional genes potentially linked to mercury metabolism including GPX1, GPX4 and SEPP114 were considered in a previous report from the same cohorts (GliomaSE and UKB) [52]; one variant in GPX1 (rs1050450) previously linked to mercury levels in body tissues14 was also found to predict nail mercury concentrations in the present study (Supplemental Table 3); however, neither this variant nor any other in these genes was significantly associated with glioma risk [52]. Here, GPX4 is linked to glioma.