[Study on the association between estrogen receptor alpha gene polymorphism and intrahepatic cholestasis of...

To investigate the relationship between estrogen receptor alpha (ERalpha) gene polymorphism and intrahepatic cholestasis of pregnancy (ICP).

The Xba I and Pvu II polymorphisms in intron 1 of ER alpha gene were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 100 pregnant women with ICP (ICP group) and 100 normal pregnant women (control group).

(1) The frequencies of XX, Xx and xx genotypes of Xba I polymorphism were 6%, 33% and 61% respectively in control group, and were 2%, 33% and 65% respectively in ICP group. There was no significant difference in the distribution of Xba I genotypes between the two groups (P > 0.05). The frequencies of the two alleles X and x were 23% and 78% in control group, and were 19% and 82% in ICP group, respectively. There was also no significant difference in the frequency of Xba I alleles between the two groups (P > 0.05). (2) The frequencies of PP, Pp and pp genotypes of Pvu II polymorphism were 18%, 42% and 40% respectively in control group, and were 12%, 53% and 35% respectively in ICP group. There was no significant difference in the distribution of Pvu II genotypes between the two groups (P > 0.05). The frequencies of the two alleles P and p were 39% and 61% in control group, and were 39% and 62% in ICP group, respectively. There was also no significant difference in the frequency of Pvu II alleles between the two groups (P > 0.05). (3) There was also no significant difference in the distribution of Xba I and Pvu II combinative genotype between the two groups (P > 0.05).

The ERalpha gene polymorphism is not associated with the risk of ICP.