It is notable that both the allele and genotype distribution of the rs755622 SNP in MIF showed associations with the severity of goiter in patients with untreated GD (GD patients vs healthy controls, P = 0.006 for allele distribution and P = 0.009 for genotype distribution; among GD patients with goiter of different grades, P = 0.002 for allele distribution and P = 0.001 for genotype distribution; Table 3). Here, MIF is linked to goiter.