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Background Chagas disease is an infectious disease caused by the parasite Trypanosoma cruzi and is endemic from Latin American countries. The goal of our study was to identify novel genetic loci associated with chronic Chagas cardiomyopathy development in Chagas disease patients from different Latin American populations. Methods We performed a cross-sectional, nested case-control study including 3 sample collections from Colombia, Argentina, and Bolivia. Samples were genotyped to conduct a genome-wide association study (GWAS). These results were meta-analyzed with summary statistic data from Brazil, gathering a total of 3413 Chagas disease patients. To identify the functional impact of the associated variant and its proxies, we performed an in silico analysis of this region. Results The meta-analysis revealed a novel genome-wide statistically significant association with chronic Chagas cardiomyopathy development in rs2458298 (OR = 0.90, 95%CI = 0.87–0.94, P-value  = 3.27 × 10-08), nearby the SAC3D1 gene. In addition, further in silico analyses displayed functional relationships between the associated variant and the SNX15 , BAFT2, and FERMT3 genes, related to cardiovascular traits. Conclusions Our findings support the role of the host genetic factors in the susceptibility to the development of the chronic cardiac form of this neglected disease. [ABSTRACT FROM AUTHOR]

Exploitation of fish species within marine protected areas (MPA) requires knowledge about fish and fleets dynamics in order to provide reasonable management actions. Our study analyzes a multi-specific artisanal fishery (<10 TGR) operating from La Paloma port (Uruguay, South America) within the MPA of the Rocha Lagoon Protected Landscape (MPA-RLPL) through the temporal assessment (September 2005 to January 2010) of daily catch composition, fishing gear, and fish community dynamics. Seventeen vessels operated inside and outside the MPA-RLPL and they reached 202,773 kg of total catch within that MPA. This amount represents 9.1% of landings registered in La Paloma port during the study period (5 years). Following the seasonal dynamics of catch composition and fishing gears it was revealed a differential use of this coastal protected area by the artisanal fisheries and the fish community. Higher catches of Squatina guggenheim , Mustelus schmitti, Galeorhinus galeus , Urophycis brasiliensis , Paralichtys orbignyanus , and Cynoscion guatucupa occurred from spring-summer, whereas in fall-winter, the higher catches were composed of Micropogonias furnieri (adults and juveniles), Umbrina canosai , Pomatomus saltatrix , and Parona signata. A multiclass classification tree (CART) method confirmed the strong relationship between the catch composition, fishing gear, and time of fishing (month, season); this method successfully classified the dominant catches in 72% of the sets (error = 18%, n = 294). Squatina guggenheim (a threatened coastal shark), and Micropogonias furnieri (a overexploited bony fish) were the dominant catch in most fishing sets. At the present there are no specific measures to regulate fishery activities inside the MPA of the RLPL. Thus, our study results were used to propose an adaptive strategy to management small-scale fisheries within MPAs in balance with natural resources conservation. The key role of the MPA-RLPL in conservation ecology was revealed through a comparative analysis with larger areas distributed in the jurisdictional waters of Uruguay or under binational management with Argentina. Image 1 • Seasonal differential use of a coastal marine protected area by fish community. • Endangered coastal sharks are dominating the artisanal catches. • Prediction of temporal variability in catch composition using CART model. • Fishery-ecological assessment between three areas of the Southwest Atlantic. • Management strategy for small-scale artisanal fisheries in marine protected areas. [ABSTRACT FROM AUTHOR]

Host genetic factors have been suggested to play an important role in the susceptibility to Chagas disease. Given the influence of interleukin 18 (IL-18) in the development of the disease, in the present study, we analyzed three IL18 genetic variants (rs2043055, rs1946518, rs360719) regarding the predisposition to Trypanosoma cruzi infection and the development of chronic Chagas cardiomyopathy (CCC), in different Latin America populations. Genetic data of 3,608 patients from Colombia, Bolivia, Argentina, and Brazil were meta-analyzed to validate previous findings with increased statistical power. Seropositive and seronegative individuals were compared for T. cruzi infection susceptibility. In the Colombian cohort, the allelic frequencies of the three variants showed a significant association, with adjustment for sex and age, and also after applying multiple testing adjustments. Among the Colombian and Argentinean cohorts, rs360719 showed a significant genetic effect in a fixed-effects meta-analysis after a Bonferroni correction (OR: 0.76, CI: 0.66-0.89, P = 0.001). For CCC, the rs2043055 showed an association with protection from cardiomyopathy in the Colombian cohort (OR: 0.79, CI: 0.64-0.99, P = 0.037), with adjustment for sex and age, and after applying multiple testing adjustments. The meta-analysis of the CCC vs. asymptomatic patients from the four cohorts showed no evidence of association. In conclusion, our results validated the association found previously in the Colombian cohort suggesting that IL18 rs360719 plays an important role in the susceptibility to T. cruzi infection and no evidence of association was found between the IL18 genetic variants and CCC in the Latin American population studied., Competing Interests: The authors have declared that no competing interests exist.

Several studies have proposed different genetic markers of susceptibility to develop chronic Chagas cardiomyopathy (CCC). Many genes may be involved, each one making a small contribution. For this reason, an appropriate approach for this problematic is to study a large number of single nucleotide polymorphisms (SNPs) in individuals sharing a genetic background. Our aim was to analyze two CCR2 and seven CCR5 SNPs and their association to CCC in Argentina. A case-control study was carried out in 480 T. cruzi seropositive adults from Argentinean Gran Chaco endemic region (Wichi and Creole) and patients from Buenos Aires health centres. They were classified according to the Consensus on Chagas-Mazza Disease as non-demonstrated (non-DC group) or demonstrated (DC group) cardiomyopathy, i.e. asymptomatic or with CCC patients, respectively. Since, after allelic analysis, 2 out of 9 studied SNPs did not fit Hardy-Weinberg equilibrium in the unaffected non-DC group from Wichi patients, we analyzed them as a separate population. Only rs1800024T and rs41469351T in CCR5 gene showed significant differences within non-Wichi population (Creole + patients from Buenos Aires centres), being the former associated to protection, and the latter to risk of CCC. No evidence of association was observed between any of the analyzed CCR2-CCR5 gene polymorphisms and the development of CCC; however, the HHE haplotype was associated with protection in Wichi population. Our findings support the hypothesis that CCR2-CCR5 genes and their haplotypes are associated with CCC; however, depending on the population studied, different associations can be found. Therefore, the evolutionary context, in which the genes or haplotypes are associated with diseases, acquires special relevance., Competing Interests: The authors have declared that no competing interests exist