Objective: To explore the association between the C46T polymorphism of coagulation factor Ⅻ (FⅫ) gene and the involvement of FⅫ activity (FⅫ:C) in patients with unexplained recurrent spontaneous abortion (URSA), and to elucidate its role in the pathogenesis of URSA.
Methods: This study included 203 patients with URSA (URSA group) and 171 healthy women with at least one child and no history of infertility or miscarriage (control group) in the southern area of Zhejiang Province. The C46T polymorphism of the FⅫ gene was analyzed with matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDI-TOF-MS) in all subjects. The values of prothrombin time, activated partial thromboplastin time (APTT), fibrinogen, FⅫ:C and other coagulant parameters were determined. The frequency distribution of the wild-type (CC), heterozygote (CT), homozygote (TT) genotypes and C and T alleles were compared between the patients and controls. A comprehensive analysis of association was conducted between C46T genotypes and the FⅫ:C levels in URSA patients.
Results: The CC, CT, TT genotypes of the FⅫ gene were observed in 7 (3.4%, 7/203), 83 (40.9%, 83/203) and 113 (55.7%, 113/203) patients with URSA versus 7 (4.1%, 7/171), 46 (26.9%, 46/171) and 118 (69.0%, 118/171) controls. The frequency of CT in the patients with URSA was significantly higher than that in controls, but the frequency of TT in the patients was lower than that in controls (χ(2)=7.939, OR=1.884, 95%CI: 1.210-2.935, P<0.05). The frequencies of allele C and allele T were observed in 97 (23.9%, 97/406) and 309 (76.1%, 309/406) patients with URSA versus 60 (17.5%, 60/342) and 282 (82.5%, 282/342) controls. The distribution frequency of allele T in URSA group was lower than that in control group (χ(2)=4.510, OR=1.475, 95%CI: 1.029-2.115, P<0.05). The FⅫ: C levels in the patients were (102±13)% in CC genotype, (78±11)% in CT genotype and (59±9)% in TT genotype, respectively. The differences of the FⅫ: C levels between the CC and CT, CT and TT, CC and TT genotypes in the patients were significant (all P<0.05).
Conclusions: The low level of FⅫ:C maybe result from the T allele of the FⅫ gene in URSA patients. The CT genotype might be relative to the pathogenesis of URSA in a Chinese Han female population from the southern area of Zhejiang province.