RESUMO
Trachoma, caused by Chlamydia trachomatis, is the most common infectious blindness in the world and is present in indigenous Mayan from Chiapas (Mexico). Inflammatory genes are activated when suffering from trachoma, thus some polymorphisms could increase the susceptibility to develop irreversible blindness. This study aimed to evaluate the genetic risk of developing late-stage trachoma in Mayan ethnic groups. In a case-control study (n = 51 vs n = 102, respectively), the following single-nucleotide polymorphisms (SNPs) in genes related to inflammation were analysed: HSD11B1 (rs11807619), HSD11B1 (rs932335), ABCG2 (rs2231142), SLCO1B1 (rs4149056), IL-10 (rs1800890), TNF (rs1800629), MMP2 (rs243865) and ACE. Three SNPs were associated with late-stage trachoma risk: (i) the T allele of rs11807619, (ii) the C allele of rs932335, which are linked to the HSD11B1 gene (OR = 22.5-27.3), particularly in men when adjusts for gender (OR = 16-16.7); and (iii) D allele of rs4340 in the ACE gene (OR = 5.2-5.3). In fact, significant linkage disequilibrium demonstrated association between ACE gene and HSD11B1 SNPs (r = 0.17-0.179; P = 0.0048-0.0073). Two SNPs HSD11B1 gene (P = 0.013 vs 0.0039) and HSD11B1-ACE haplotypes showed association with late-stage trachoma in Mayan ethnic groups.
