Asthma genetics and genomics 2009.

Asthma Genetic Association studies have been plagued by methodologic problems that are common in all studies of complex traits: small sample size, lack of replication, and lack of control of population stratification. Despite this, the field has identified 43 replicated genes from association studies. The most frequently replicated are: TNF alpha, IL4, FCERB, Adam 33, and GSTP1. Several genes have been identified by linkage and fine mapping (ADAM33, DPP10, GPR154, and PHF11) and one gene has been identified by GWAS (ORMD3). The major issue is that these genes have been looked at one at a time rather than in some more holistic manner where epistasis is considered. For asthma genetics to begin to have an impact on clinical medicine we need to consider epistatic interaction.