FLG2 (filaggrin-2) is essential for maintaining cell-cell adhesion and structural integrity in the cornified layers of the epidermis, particularly the stratum corneum. The protein is a member of the S100 fused-type protein family and plays a critical role in epidermal differentiation and skin barrier formation. FLG2 expression is regulated by the transcription factor GATA3 and is suppressed by inflammatory cytokines (IL-4, IL-13, IL-22, and IL-17A) through STAT-dependent pathways 12. Dysregulation of FLG2 is associated with atopic dermatitis and other inflammatory skin conditions; reduced FLG2 expression correlates with barrier dysfunction in both lesional and nonlesional AD skin 3. Uncommon FLG2 variants are associated with AD remission in longitudinal cohorts, particularly among self-described white and African American populations 4. Loss-of-function FLG2 mutations do not appear to drive AD pathogenesis independently. Therapeutically, FLG2 expression can be restored through JAK inhibition (ruxolitinib) and aryl hydrocarbon receptor agonists, offering promise for AD management 56. Recent evidence suggests FLG2 has broader clinical relevance as a serum biomarker for acute respiratory distress syndrome prognosis 7.