Study Aims

GALA I: Family-based study (children with asthma and their parents)

GALA II: Case-control study (children with asthma and healthy controls)

Aim 1: Assess the interaction between genetic ancestry, environmental/demographic risk factors, asthma and asthma-related phenotypes

We are testing the hypothesis that genetic ancestry interacts with environmental/demographic risk factors to modify asthma risk and asthma-related phenotypes including severity, bronchodilator drug responsiveness and IgE levels among Latinos. We will recruit 2000 asthma cases and 2000 matched controls from the Bronx, NY, Chicago, IL, San Francisco, CA, Houston, TX and Puerto Rico. Individual genetic ancestry will be determined using ancestry informative markers (AIMs). Risk factors that will be analyzed include: socioeconomic status (SES), urban/rural living, day care exposure, environmental tobacco smoke (ETS) exposure and air pollution.

Aim 2: Examine candidate gene-environment interactions for asthma and asthma-related phenotypes

We will genotype fifty candidate genes in the innate immunity, xenobiotic metabolism and antioxidant defense pathways. We will determine if there are ethnic-specific gene-environment interactions, which differentially affect asthma risk, severity and pharmacologic response between Latino ethnic groups.

Aim 3: Determine whether migration and acculturation are associated with asthma and severe asthma

Place of birth and length of stay in the U.S. are indicators of migration and acculturation. We will test the hypotheses that these indicators are associated with asthma and asthma severity. We will also test the hypothesis that place of birth and length of stay in the U.S. interact with ancestry, environmental, clinical and demographic risk factors to modify their associations with asthma and asthma severity among Latinos. To test these hypotheses we will categorize Latino subjects into three groups according to their migration and acculturation status. The three categories will be:

  1. U.S.-born and foreign born but living in the U.S. for more than 5 years
  2. foreign-born and living in the U.S. for less than 5 years
  3. mainland-born Puerto Ricans