Finally, analysis of the DNA sequence of the ECP gene and surrounding regions have unravelled a number of polymorphisms. These studies have linked different polymorphisms and haplotypes to TH2 diseases, asthma, and allergic rhinitis. The studies have in some cases come to different conclusions but used different patients and different ethnic groups which might explain the variations. Diseases such as allergic asthma are multifactoral and to determine the role of certain polymorphisms one might need to look at larger defined groups to get a clear association. Altered expression levels might also influence both destructive functions and possible homeostatic roles. A careful analysis using all polymorphisms and corresponding haplotypes and large groups of defined populations would more clearly determine the role of ECPs genetic make-up, and its potential functions in physiology and disease.