CYP2B6 and chronic obstructive pulmonary disease: However, in our population, polymorphisms in CYP2B6 and CYP2A6 were associated with a lower risk of suffering from COPD; this indicates that in Latin America, Mexico had a minor prevalence of disease (7.8%) but had an annual cigarette consumption of 500–1499 per person [30], equal to Brazil, Uruguay, Chile, and Venezuela, which have a major prevalence at 10% [31].