Genetics of Atopic Dermatitis: Beyond Filaggrin—the Role of Thymic Stromal Lymphopoietin in Disease Persistence

In this issue of JAMA Dermatology, Margolis et al¹ report the association of a thymic stromal lymphopoietin (TSLP) variant with disease remission in children with atopic dermatitis (AD), particularly in those carrying filaggrin gene (FLG) mutations. Thymic stromal lymphopoietin, an epithelial cell-derived cytokine, is a master initiator of helper T cell type 2 (T_H2) differentiation and allergic manifestations.² These results suggest that TSLP could be a possible dual factor in AD, capable of modulating the effects of FLG mutations in triggering allergic manifestations. Alternatively, this single-nucleotide polymorphism (SNP) variant could be in linkage disequilibrium, with a causative variant to be identified, localized within or outside TSLP. Functional and expression studies of this TSLP SNP variant will be instrumental to assess its role(s) in the disease.