Does ethnic ancestry play a role in smoking?

Abstract

The higher proportion of smokers among Black people in Brazil has been attributed to socioeconomic disparities, but genetic factors could also contribute for this finding. This study aimed at investigating associations between smoking status with genetically defined ethnic ancestry and socioeconomic features in Brazilians. Blood samples were collected from 448 volunteers (66.7% male; age: 37.1±11.4 years) classified as current smokers (CS: 60.9%), former smokers (FS: 8.9%) and never smokers (NS: 30.1%). Individual interethnic admixtures were determined using a 48 insertion-deletion polymorphisms ancestryinformative-marker panel. CS showed a lower amount of European ancestry than NS (0.837±0.243 X 0.883±0.194, p≤0.05) and FS (0.837±0.243 X 0.864±0.230, p≤0.05), and a higher proportion of African Sub-Saharan ancestry than FS (0.128±0.222 X 0.07±0.174, p≤0.05) and NS (0.128±0.222 X 0.085±0.178, p≤0.05). NS reported a higher number of years in school than CS (11.2±3.7 X 8.9±3.8, p≤0.001). CS were less common in economic Class A (30%) and more common in Class B (56.8%). In multivariate analysis, only lower number of school years and lower economic class were associated with higher chances for CS. The use of genetic molecular markers for characterizing ethnic background confirmed that socioeconomic disparities are the main determinants of higher smoking rates among Blacks in Brazil.

Neither self-reported ethnicity nor declared family origin are reliable indicators of genomic ancestry

“…However, the child's school experience and the socioeconomic status of the family also contribute to this diversity. Similarly, in a study by Souza et al (2015), the use of genetic markers for characterization of ancestry background strongly suggests that socioeconomic disparities, and not ethnicity, are the main determinants of higher smoking rates among blacks in Brazil.…”

Molecular basis of familial adenomatous polyposis in the southeast of Brazil: identification of six novel mutations

“…[20][21][22] Only one study has evaluated FAP families in the Brazilian population, 23 which has a tri-hybrid genetic background specifically, encompassing Native American, European, and African ancestries. 24 Although we have not inferred the ancestry of our cohort, De Souza et al 25 have previously evaluated the ancestry components of patients admitted at the same hospital where we collected our samples, and showed that these patients had approximately 85% European ancestry, 10% African, and 4% Native American ancestry. These proportions are in agreement with studies that evaluated the ancestry of different cohorts, confirming the admixed unique background of the Brazilian population.…”

Ethnic ancestry and smoking, farming of wine grapes in semiarid regions, and the potentials of Manihot multifida in medicine use

“…As pointed out in their paper (Souza et al 2015), some studies indicate that white Americans are more likely to smoke than the black population (e.g., Ward et al 2002). In Brazil, however, the opposite has been shown: the tendency is that the white population smokes less than others (e.g., INCA 2011).…”

“…In this issue of the AABC, we are publishing a contribution that is a little bit different from previous ones. Souza et al (2015) have investigated the relation between ethnic ancestry and the habit of smoking.…”

“…In Brazil, however, the opposite has been shown: the tendency is that the white population smokes less than others (e.g., INCA 2011). Souza et al (2015) addressed this issue from a genetic point of view, trying to establish potential associations between smoking habits with genetically defined ancestry.…”