Objective: To study the role of gene polymorphisms of cytochrome P4501B1 (CYP1B1) in exon 2 codon 119(G-T) and exon 3 codon 432(C-G) in intrahepatic cholestasis of pregnancy (ICP).
Methods: Gene polymorphisms of CYP1B1 in exon 2 codon 119 and exon 3 codon 432 were detected with Allele-specific polymerase chain reaction (ASA-PCR) and di-allele-specific-amplification with artificially modified primer (diASA-AMP) techniques in a case-control study, which included 100 ICP patients and 100 healthy pregnant women as controls.
Results: (1) The ICP patients had higher frequency of allele T on codon 119 of CYP1B1 gene than the controls (P < 0.05). Significant differences of frequencies were found in genotype GG, GT and TT between the ICP patients and the controls (P > 0.05). Compared to the wide-type GG, the ICP risks of the women with genotype TT homozygous and GT heterozygous increased by 3.6 and 2.435 times, respectively. (2) No genotype GG was found in this study. There were no significant differences between the ICP patients and the controls in the genotype distributions (CC and CG) and allele frequencies (C and G) of CYP1B1 polymorphism in exon 3 codon 432 (P > 0.05).
Conclusion: Gene polymorphism of CYP1B1 in exon 2 codon 119 may be associated with the risk of ICP. The mutation of CYP1B1 gene increases the risk of ICP. The gene polymorphism of CYP1B1 in exon 3 codon 432 is not associated with the risk of ICP.