Association between ocular toxoplasmosis and APEX1 and MYD88 polymorphism

Abstract

Ocular toxoplasmosis (OT) is the most common form of posterior uveitis, and in some countries, it is the most frequent cause of visual impairment. Studies demonstrate that the polymorphism in genes involved with the immune response can be related both to the occurrence and to the recurrence of OT. Thus, the present study aimed to analyze the association between OT and the polymorphism of the APEX1 (rs1130409) and MyD88 (rs7744) genes. The studied sample consisted of 48 volunteers with OT and 96 asymptomatic volunteers, but positive for anti - T. gondii IgG (control group). Blood collection was performed for serological analysis (ELISA) and DNA extraction. Genotyping of the polymorphism was performed using real-time PCR. To analyze the association between gene polymorphism and OT, logistic regression was performed. The results showed no association between the MYD88 gene polymorphism and the development of OT. However, a significant association was found between OT and APEX1 gene polymorphism, indicating that individuals expressing polymorphic (GG) or heterozygous (GT) alleles are more likely to develop the disease (P-value = 0.02 and 0.03 respectively). These results suggest that APEX1 (rs1130409) polymorphism is a risk factor for the occurrence of ocular toxoplasmosis in the studied population.

Keywords: APEX1; Gene polymorphism; MyD88; Ocular toxoplasmosis.