TNFα rs1799964 TT genotype may be a susceptibility factor for vertical transmission of Toxoplasma gondii and clinical signs in newborns from pregnant women with acute toxoplasmosis

Background One of the main impacts of Toxoplasma gondii infection occurs during pregnancy and is related to the vertical transmission of the parasite (congenital toxoplasmosis), which can cause severe clinical outcomes and fetal death. During acute infection, in order to control the rapid replication of tachyzoites, different host immune response genes are activated, and these include cytokine-encoding genes. Considering that polymorphisms in cytokine genes may increase susceptibility to vertical transmission of T. gondii by determining the immune status of the pregnant woman, this study evaluated the influence of polymorphisms of tumor necrosis factor alpha (TNF alpha) rs1799964 (- 1031) and interleukin 1 beta (IL1 beta) rs16944 (- 511) genes on gestational toxoplasmosis and on the vertical transmission of the parasite and verified the allele and genotype frequency of these polymorphisms in pregnant patients whose respective newborn did or did not present clinical abnormalities suggestive of congenital toxoplasmosis. Methods and results A total of 204 pregnant patients with (n =114) or without (n = 90) infection by T. gondii were enrolled. No associations were found involving the polymorphisms rs1799964 (- 1031) of the TNF alpha gene and rs16944 (- 511) of the IL1 beta gene with the increased chance of T. gondii infection during pregnancy. However, it was observed that the maternal TT genotype referring to the polymorphism of the TNF alpha gene seems to influence the vertical transmission of the parasite (P = 0.01; chi(2) = 6.05) and the presence of clinical manifestation in newborns from pregnancies with acute toxoplasmosis (P=0.007; chi(2) = 9.68). Conclusion The TNF alpha rs1799964 TT genotype may act as a susceptibility factor for the vertical transmission of parasite and for the presence of clinical signs in newborns from pregnant women with acute toxoplasmosis.

Automated summary

This study evaluated the influence of polymorphisms in tumor necrosis factor alpha (TNF alpha) and interleukin 1 beta (IL1 beta) genes on Toxoplasma gondii infection. The results showed that the TNF alpha rs1799964 polymorphism is associated with the vertical transmission of the parasite and clinical manifestations in newborns with acute toxoplasmosis.