Study of Association Between Hypertensive Disorders of Pregnancy and the Human Coagulation Factor XI Gene

Haplotype-based, case-control study of myosin phosphatase target subunit 1 (PPP1R12A) gene and hypertensive disorders of pregnancy

Objective: Hypertensive disorders of pregnancy (HDP) are thought to be a multifactorial genetic disease. Myosin light chain phosphorylation, which is involved in the regulation of vascular smooth muscle contraction and relaxation and thus contributes to the maintenance of blood pressure, is related to HDP. The official symbol of the gene for the production of MYPT1 protein is PPP1R12A gene. Thus, we investigated the possibility that the PPP1R12A gene is related to HDP. Methods: Subjects were 194 pregnant women with HDP and a control group of 262 pregnant women from those women examined. Four SNVs (rs7296839, rs11114256, rs2596793, and rs2694657) were selected from the PPP1R12A gene region. The HDP group was divided according to disease type, and each group was analyzed in comparison with the control group. Results: In the association analysis using the PPP1R12A gene, there were significant differences between the control group and the superimposed preeclampsia (SPE) group for rs11114256 in allele frequency distribution (P = 0.017) and genome frequency distribution in the dominant model (P = 0.014), and for rs2694657 genotype distribution frequency in the recessive model (P = 0.018). In the association analysis using haplotypes, there was a significant difference for G-A-A-G (rs7296839-rs11114256-rs2596793-rs2694657). In an analysis of haplotype-based case-control study, there was a significant difference for G-A-A-G between the control group (0.00%) and the HDP group (2.46%) (P = 0.038). Furthermore, the G-T-A-G haplotype was significantly higher in SPE group than in control group (P = 0.011). Conclusions: The implication is that the PPP1R12A gene may be a disease-susceptibility gene for SPE.

Factor 11 single-nucleotide variants in women with heavy menstrual bleeding

In a previous study it was shown that lower factor XI (FXI) levels in women with heavy menstrual bleeding (HMB). Our aim was to determine the single-nucleotide variants (SNVs) in the F11 gene in women with HMB. In addition, an extensive literature search was performed to determine the clinical significance of each SNV. Patients referred for HMB (PBAC-score >100) were included. With direct sequencing analysis of all 15 exons and flanking introns of the F11 gene, 29 different non-structural SNVs were detected in 49 patients with HMB. Interestingly, most of these SNVs have previously been associated with venous thrombosis instead of bleeding. These findings have not helped to elucidate the molecular basis of HMB. They also question the specificity of previously reported F11 variations in patients with thrombosis. More studies are needed to explain the lower FXI levels seen in patients with HMB. IMPACT STATEMENT Women with mild deficiencies of factor XI (FXI) (< 70%) are prone to excessive bleeding during menstruation. Bleeding manifestations are not well correlated with plasma FXI levels and bleeding episodes can vary widely among patients with similar low FXI levels. In a previous study we showed that women with heavy menstrual bleeding (HMB) had normal, but on average, lower levels of FXI than controls. In light of these findings, we performed F11 gene analysis to determine the single-nucleotide variants (SNVs) in women with HMB and performed an extensive literature search to determine the clinical significance of each SNV. By direct sequencing analysis of the F11 gene we found 29 different non-structural SNVs in 49 women with heavy menstrual bleeding. Remarkably, a number of these SNVs have previously been implicated in thrombosis. These findings have not helped to elucidate the molecular basis of lower FXI levels in HMB. They also question the specificity of previously reported F11 variations in patients with thrombosis. More studies are needed to explain the lower FXI levels seen in patients with HMB.

Comparison between essential hypertension and pregnancy-induced hypertension: a genetic perspective

Essential hypertension (EH) accounts for 80-90% of hypertension, and pregnancy-induced hypertension (PIH) is responsible for hypertension during pregnancy. Both considered multifactorial disorders. While both have many features in common, conditions and causes of these diseases have yet to be clarified. Since both diseases are associated with hypertension, the genetic backgrounds may contain common features. The present study reviewed similarities and differences between women with EH and PIH, with a particular focus on their genetic backgrounds.

Haplotype-based case-control study of estrogen receptor alpha (ESR1) gene and pregnancy-induced hypertension

Hypotheses about pregnancy-induced hypertension (PIH) have been proposed to explain the vascular damage that characterizes this disease. Reports indicate that estrogens and estrogen receptors play important physiological roles in cardiovascular diseases. There have been studies examining the association between coronary artery disease and the estrogen receptor alpha (ESR1) gene. The aim of the present work was to assess the association between PIH and single-nucleotide polymorphisms (SNPs) in the human ESR1 gene, by conducting a haplotype-based case-control study. Based on a database search at the web site of the National Center of Biotechnology Information, we chose five SNPs in the human ESR1 gene, and performed an association study using 95 PIH patients and 200 age-matched non-PIH subjects. The frequency of rs2881766 genotypes and alleles differed significantly between the two groups. There was no significant difference in overall distribution of genotypes or alleles of the other four SNPs. The T allele of rs2881766 was significantly more prevalent in the PIH group than in the non-PIH group. Haplotype-based case-control analysis revealed that there was a significant difference in overall distribution of the combinations rs2881766-rs1643821-rs988328 and rs2881766-rs1643821 between the PIH group and the non-PIH group (all or body mass index [BMI]-matched). One susceptibility haplotype for PIH and two resistance haplotypes for PIH were revealed by comparison between the PIH group and the non-PIH (BMI-matched) control group. In conclusion, the T allele of rs2881766 could be a useful genetic marker of PIH. The G-A-T haplotype of rs2881766-rs1643821-rs988328 and the G-A haplotype of rs2881766-rs1643821 appear to be resistance markers of PIH.