Genetic ancestry in lung-function predictions.

Area of Science:

• Pulmonary Medicine
• Genetics
• Epidemiology

Background:

• Current pulmonary function reference standards rely on self-identified race.
• This may lead to inaccurate lung function predictions for individuals of African descent.

Purpose of the Study:

• To determine if genetically determined African ancestry is associated with lung function.
• To assess if using ancestry improves lung function prediction in African Americans.

Main Methods:

• Assessed ancestry in 777 African American participants (CARDIA study).
• Evaluated lung function and ancestry relationship using linear regression across three cohorts (CARDIA, HABC, CHS).
• Compared standard prediction models with ancestry-incorporating models and assessed impact on asthma severity classification.

Main Results:

• African ancestry showed an inverse relationship with forced expiratory volume in 1 second (FEV(1)) and forced vital capacity across all cohorts.
• Ancestry-based models demonstrated a superior fit for predicting lung function compared to standard models.
• Ancestry-based models led to a reclassification of asthma severity in 4-5% of participants.

Conclusions:

• Self-identified race alone may lead to misestimation of lung function in African Americans.
• Integrating genetic ancestry into predictive equations can enhance lung function estimates.
• Improved lung function estimation through ancestry may lead to more accurate disease severity categorization.