Esophagitis, Eosinophilic, 2
For a general phenotypic description and a discussion of genetic heterogeneity of eosinophilic esophagitis, see EOE1 (610247).
MappingRothenberg et al. (2010) genotyped approximately 550,000 genomewide SNPs in a discovery cohort of 181 eosinophilic esophagitis (EOE) cases and 1,974 controls and a replication cohort of 170 EOE cases and 1,130 controls. Significant association was found with variants at a region on chromosome 5q22 encompassing the TSLP (607003) and WDR36 (609669) genes (combined p = 3.19 x 10(-9) for rs3806932). Analysis of esophageal biopsies revealed that TSLP was significantly overexpressed in EOE cases compared to controls (p less than 0.0001 for TSLP isoform 2), whereas WDR36 was unchanged. TSLP expression levels were also significantly correlated with the rs3806932 genotype in EOE cases, with homozygote carriers of the protective minor G allele showing less TSLP expression than heterozygotes or homozygotes for the ancestral allele. Rothenberg et al. (2010) concluded that the TSLP gene is the most likely candidate gene involved in the pathogenesis of EOE at the chromosome 5q22 locus in cases of European ancestry.