Novel Genetic Risk factors for Asthma in African American Children: Precision Medicine and The SAGE II Study

Background Asthma, an inflammatory disorder of the airways, is the most common chronic disease of children worldwide. There are significant racial/ethnic disparities in asthma prevalence, morbidity and mortality among U.S. children. This trend is mirrored in obesity, which may share genetic and environmental risk factors with asthma. The majority of asthma biomedical research has been performed in populations of European decent. Objective We sought to identify genetic risk factors for asthma in African American children. We also assessed the generalizability of genetic variants associated with asthma in European and Asian populations to African American children. Methods Our study population consisted of 1227 (812 asthma cases, 415 controls) African American children with genome-wide single nucleotide polymorphism (SNP) data. Logistic regression was used to identify associations between SNP genotype and asthma status. Results We identified a novel variant in the PTCHD3 gene that is significantly associated with asthma (rs660498, p = 2.2 x10 −7 ) independent of obesity status. Approximately 5% of previously reported asthma genetic associations identified in European populations replicated in African Americans. Conclusions Our identification of novel variants associated with asthma in African American children, coupled with our inability to replicate the majority of findings reported in European Americans, underscores the necessity for including diverse populations in biomedical studies of asthma.