ObjectiveTo investigate whether single nucleotide polymorphism (SNP) of macrophage migration inhibitory factor (MIF) gene - 173G/C is associated with severe preeclampsia.Methods Totally 124 severe preeclampsia patients and 160 healthy pregnant women (control group) were included in our study who were recruited consecutively from Affiliated Hospital of Qiugdao University Medical College between March 2010 and March 2011.The SNP was detected through SYBR Green PCR.The levels of fasting blood glucose ( FBG),fasting insulin ( FIN),and serum total cholesterol (TC),triglyceride ( TG),high density lipoprotein (HDL) and light density lipoprotein (LDL) were determined in every participants.The homeostasis model assessment-insulin resistance (HOMA-IR) was calculated.The allele and genotype frequencies between severe preeclampsia patients and control group were compared.The FBG,FIN,body mass index (BMI),HOMA-IR,TC,TG,HDL and LDL in different genotype were compared.Results ( 1 ) The MIF - 173G/C SNP genotype frequencies of GG,CG,and CC were 62.1％ (77/124),30.6％ (38/124),7.3％ (9/124),the allelic frequencies of G and C were 77.4％ ( 192/248 ) and 22.6％ (56/248),respectively,in severe preeclampsia patients; the MIF - 173G/C SNP genotype frequencies of GG,CG,and CC were 64.4％ ( 103/160 ),30.6％ (49/160),5.0％ ( 8/160),the allelic frequencies of G and C were 79.7％ (255/320) and 20.3％ (65/320),respectively,in the control group.No significant differences were observed in the genotypes and allele distributions of MIF - 173G/C SNP between the severe preeclampsia patients and control group (all P ＞ 0.05 ).(2) The severe preeclampsia patients with CG and CC genotypes had higher BMI compared with the GG genotype [ (25 ±4) versus (22 ±4) kg/m2 ; t =3.96,P ＜ 0.05 ].( 3 ) The severe preeclampsia patients with CG and CC genotypes had higher FIN level and higher HOMA-IR compared with the GG genotype [ ( 15.7 ±2.9) versus ( 13.6 ±4.0) mmoL/L,3.3 ±0.5 versus 2.7 ± 0.6 ; t =3.17,t =5.58,all P ＜ 0.05 ].(4) There was no significant difference in FBG,TC,TG,HDL and LDL levels in severe preeclampsia patients with different genotypes (all P ＞0.05 ).Conclusions The present study suggests that the MIF - 173G/C SNP is associated with insulin resistance in severe preeclampsia patients.The CG and CC genotypes increase the degree of insulin resistance,but it is may not associate with susceptibility among severe preeclampsia patients of Han Chinese women.