CD14 tobacco gene-environment interaction modifies asthma severity and immunoglobulin E levels in Latinos with asthma.

Background: A recent family-based genomewide screen revealed linkage between the 5q31 region and the diagnosis of asthma, but only in those exposed to environmental tobacco smoke (ETS). Among the candidate genes in this region is CD14.

Methods: To determine whether polymorphisms in the CD14 gene are related to this gene-by-environment interaction in Latinos, we used both family-based and cross-sectional cohort analysis to test for interactions between CD14 genotypes/haplotypes, exposure to ETS, and asthma-related phenotypes in 659 Mexican and Puerto Rican families.

Pharmacogenetic differences in response to albuterol between Puerto Ricans and Mexicans with asthma.

Background: In the United States, Puerto Ricans and Mexicans have the highest and lowest asthma prevalence, morbidity, and mortality, respectively. Ethnic-specific differences in the response to drug treatment may contribute to differences in disease outcomes. Genetic variants at the beta(2)-adrenergic receptor (beta(2)AR) may modify asthma severity and albuterol responsiveness.

Lower bronchodilator responsiveness in Puerto Rican than in Mexican subjects with asthma.

In the United States, Puerto Ricans and Mexicans have the highest and lowest asthma prevalence, morbidity, and mortality, respectively. To determine whether ethnicity-specific differences in therapeutic response, clinical response, and/or genetic factors contribute to differences in asthma outcomes, we compared asthma-related clinical characteristics among 684 Mexican and Puerto Rican individuals with asthma recruited from San Francisco, New York City, Puerto Rico, and Mexico City. Puerto Ricans with asthma had reduced lung function, greater morbidity, and longer asthma duration than did Mexicans with asthma.

Attrition and retention of ethnically diverse subjects in a multicenter randomized controlled research trial.

Recruitment and retention of subjects is critically important for the conduct of randomized clinical trials. When significant effort is given toward recruiting members of ethnic minorities in a sample, a similar rate of retention for all subgroups of subjects is essential. Little is known about why research subjects withdraw consent to participate in research and whether attrition is influenced by ethnicity or other factors.