The effect of the D1-C785T polymorphism in the type 1 iodothyronine deiodinase gene on the circulating thyroid hormone levels in Romanian women with preeclampsia. Association with the degree of severity and pregnancy outcome of preeclampsia

Aim: To investigate the biochemical and genetic thyroid status in women with preeclampsia by the determination of serum FT3 and FT4 levels in association with D1-C785T genotypes. Methods: We genotyped using PCR-RFLP methods 50 women with preeclampsia and 50 normotensive pregnant women. Results: FT3 levels (pg/ml, 2.63 +/- 0.56 vs. 2.91 +/- 1.41) were low, and FT4 levels (ng/dl, 1.11 +/- 0.3 vs. 0.88 +/- 0.14) were high in women with preeclampsia compared to normal pregnant women. The association with severe preeclampsia was stronger for the homozygous T/T genotype (OR 6.57, p = 0.029). Women with preeclampsia with the D1-T785 mutated allele had lower FT3 levels (pg/ml, 2.31 +/- 0.81 vs. 3.04 +/- 0.39, p < 0.001), higher FT4 levels (ng/dl, 1.32 +/- 0.87 vs. 0.84 +/- 0.24, p = 0.009) than women with preeclampsia with the D1-C/C genotype. Significant decrease in serum FT3 levels in positive women with severe preeclampsia compared to women negative for this genetic variation (pg/ml, 1.59 +/- 0.74 vs. 2.77 +/- 0.23, p = 0.003) was observed. Women with severe preeclampsia, positive for the mutated T785 allele, delivered at a significantly lower gestational age (31.75 +/- 3.69 vs. 38.66 +/- 3.21 weeks, p = 0.035) neonates with a lower birth weight (1861.11 +/- 869.9 vs. 3500 +/- 424.26 g, p = 0.023) compared to women negative for the same allele. Conclusions: Thyroid hormone levels and the D1-C785T polymorphism, alone or in combination, correlate with the severity of preeclampsia. The D1-C785T polymorphism influences the outcome of pregnancy in severe preeclampsia.