The convergence of the skin and esophageal tissue toward squamous, stratified epithelia can explain most of this discrepancy because EoE shared inflammatory genes with both AD and AA but had concordance with AD and discordance with AA in regard to epithelial/epidermal or keratinization genes (e.g., claudin 1, filaggrin, small proline-rich proteins). Here, CLDN1 is linked to Alzheimer disease.