Soluble Fms-like tyrosine kinase-1 polymorphisms associated with severe-spectrum hypertensive disorders of pregnancy.

Background: sFLT-1 has been implicated in the pathogenesis of HDP. We aimed to examine the role of maternal and fetal polymorphisms in risk of HDP and severe-spectrum disease.

Methods: Cases of HDP (143) and controls (169) from mother-baby dyads were recruited at the Los Angeles County Women's and Children's Hospital (WCH). Cases of severe disease (99) and controls (31) from mother-father-baby triads were recruited through HELLP syndrome websites. Four sFLT-1 SNPs (rs7993594, rs3751395, rs7983774, and rs664393) were genotyped. Data was analyzed using a log-linear regression model in the Haplin package in R.

Results: Maternal double dose of the A allele (rs7993594) exhibited a nominally significant increased risk of HDP (RR = 3.52, 95% CI 1.08, 11.20). In the severe-spectrum cohort, a marginally significant protective effect among mothers carrying infants with a single dose of the A allele (rs7993594) was observed (RR = 0.59, 95% CI 0.36, 0.98) and double-dose maternal carriage of the G-t-G-G haplotype increased risk of severe disease (RR = 4.13, 95% CI 1.22, 13.80).

Conclusion: The maternal rs7993594 A allele appears to be associated with increased risk of HDP. Double-dose maternal carriage of the G-t-G-G haplotype increased risk of severe disease whereas the fetal rs7983774 A allele appears to be associated with decreased risk.