Relationship between African Biogeographical Ancestry and Helicobacter pylori infection in children of a large Latin American urban center.

Abstract

The relationship between race/ethnicity and Hpylori infection has been extensively reported, with a higher prevalence of infection observed in black individuals. Whether such differences are due to genetic factors underlying African ancestry remains to be clarified. In the present study, we evaluated the association between the proportion of individual African ancestry and Hpylori infection in a sample of 1046 children living in a large Latin American urban center. Estimation of individual biogeographical ancestry was based on 370,539 SNPs and performed using the ADMIXTURE software. Multivariate logistic regression models and mediation analysis considering the influence of previously recognized socioenvironmental risk factors to Hpylori infection were performed. All analyses were conducted using the statistical package STATA v.14.0. Each 10% increase in the proportion of individual African ancestry was positively and independently associated with Hpylori infection in our population (adjusted OR=1.22, 95% CI=1.10-1.36, P<.001). Mediation analysis demonstrated that only 9.23% of the effect of the individual African ancestry on Hpylori infection was explained by factors such as household income, the absence of street paving and crowding. The results suggest that genetic variants that covariate with African ancestry may explain an important part of the racial differences observed for the prevalence of Hpylori infection.