[Correlation between killer cell immunoglobulin-like receptors genes and pre-eclampsia]

To analyze the killer cell immunoglobulin-like receptors (KIR) gene polymorphism of pre-eclampsia patients and approach the correlation between KIR genes and pre-eclampsia.

The KIR gene polymorphisms of 71 pre-eclampsia patients and 100 healthy pregnant women were detected by PCR-SSP. The KIR2DL4 mRNA level in placentas from pre-eclampsia and gestational normal pregnancies were quantified by real time RT-PCR. Forty pre-eclampsia patients and 38 healthy pregnant women were detected for single nucleotide polymorphisms (SNP) in the gene coding and joint areas between introns and extrons by directly sequencing techniques of KIR2DL4 genomic DNA. Finally, all alleles and genotypes of KIR2DL4 gene were case-control studied.

Distributions of some relatively activating KIR genotypes shewed a significant association with pre-eclampsia. Real-time RT-PCR showed that KIR2DL4 mRNA can be measured both in placenta of women with pre-eclampsia being of pre-eclampsia was significantly lower than that of normal pregnancy, only as much as 0.276 times that of controls. We identified 18 polymorphisms, of which, 7 were first reported. But no significant differences in genotype distributions or allele frequencies were observed in these SNPs between cases and controls.

The distributions of some relatively activating KIR genotypes showed a significant association with pre-eclampsia, which indicates that the polymorphism of KIR genes may be associated with the genetic predisposition to pre-eclampsia. And because the expression of KIR2DL4 mRNA in the placentas of cases was significantly lower than control group, it is speculated that the decrease of KIR2DL4 expression in placenta may participate in the pathogenesis of pre-eclampsia.