Abstract
INTRODUCTION: Among patients with Chagas disease, men have a higher risk of worse pathological symptoms than women. We aimed to explore the role of the Y chromosome in men diagnosed with Chagas disease and assess the relationship between their ancestry and disease status. METHODS: In this comparative study, we analyzed 150 men with unrelated non-chagasic disease (nCD) and 150 men with unrelated chagasic disease (CD). We assessed the serological diagnosis of Chagas disease, biochemical parameters, thoracic X-rays, electrocardiogram, and transthoracic echocardiography and determined the haplogroup by analyzing a set of 17 microsatellites from the Y chromosome. We examined the associations between common Y chromosome haplogroups and the clinical parameters of risk by logistic regression. RESULTS: For all patients, the most common haplogroups were R1b (43%), G2a (9%), and E1b1b (9%). The R1b and G2a haplogroup was more frequent in men with nCD and CD, respectively. As expected, we observed a high proportion of symptomatic patients in the CD group independent of the haplogroups. Men from both groups classified as having the R1b haplogroup showed less clinical evidence of disease. Multivariate analysis showed that CD patients without R1b were about five times more likely to have a cardio-thorax index >0.5% (OR [odds ratio] = 5.1, 95% CI [confidence interval] = 3.31-8.17). Men without the R1b haplogroup were 2.5 times more likely to show EcoCG alterations (OR = 2.50, 95% CI = 0.16-3.94). CONCLUSIONS: Our results provided evidence that the R1b haplogroup may have a potential protective cardiovascular effect for its carriers.