Interest of tumor necrosis factor-alpha -308 G/A and interleukin-10 -592 C/A polymorphisms in human African trypanosomiasis.

This study aimed to determine whether single nucleotide polymorphisms (SNPs) within tumour necrosis factor-alpha (TNF) and interleukin-10 (IL10) promoters and genes are associated with human African trypanosomiasis (HAT). The polymorphisms used in the analysis were TNF(-308G/A), TNF(-238G/A), TNF(-1031T/C), TNF(+488G/A), IL10(-1082G/A) and IL10(-592C/A). A familial case-control sample of 277 individuals (102 cases and 175 parents) and a matched case-control group of 225 subjects (88 cases and 137 unrelated controls) were gathered together in this study. A conditional logistic regression was used to test for association. We carried out this analysis in the overall population and after stratification by time of exposure, age and ethnic group. Our results show that in the overall population, and after stratification by time of exposure, the IL10(-592A) allele is associated with a lower risk of disease, suggesting the possibility of a protective effect. After stratification by time of exposure, individuals homozygous for the SNP located in the TNF(-308) promoter were shown to present a higher risk of developing the disease early after exposure. Our study shows that TNF(-308G/A) and IL10(-592C/A) SNPs are polymorphisms of interest in the investigation of the genetic susceptibility to human African trypanosomiasis. Larger studies are currently underway to confirm these results.