TGFB1 Functional Gene Polymorphisms (C-509T and T869C) in the Maternal Susceptibility to Pre-eclampsia in South Indian Women

Pre-eclampsia (PE), a pregnancy-specific vascular disorder characterized by hypertension and proteinuria, is hypothesized to be the result of inadequate placental angiogenesis with attendant systemic inflammation. The pleiotropic cytokine, Transforming Growth Factor-1 (TGF-1), is considered to be a key candidate gene in the molecular pathogenesis of PE by virtue of its ability to not only regulate angiogenesis and apoptosis of target cells, but also by acting as a master controller of Th1/Th2 cytokine balance and production of the anti-inflammatory peripheral regulatory T cells (FOXP3+ Tregs). Based on this presumption, we screened a total of 469 pregnant women from South India that include 239 patients with PE and 230 healthy controls for the two functional polymorphisms of TGFB1 gene (C-509T and T869C). The genotype frequencies of these two polymorphisms differed significantly between the PE and control groups (P=0.01 and P=0.002, for the TGFB1 C-509T and T869C polymorphisms, respectively). Under the over-dominant model, the CT genotype of the TGFB1 C509T polymorphism showed a high protective effect (P=3e-04), while the TT genotype of the same variant appeared to be the predisposing genotype (P=0.003). The T-T and C-C haplotypes were found to be the risk haplotypes blocks towards PE (OR=4.72; P=0.031, OR=5.39; P=0.03), respectively. Strong linkage disequilibrium was seen between the two polymorphisms. Our investigations revealed a significant influence of TGFB1 C-509T and T869C polymorphisms on the PE risk in South Indian women. The study represents one of the first of its kind from the Indian subcontinent.