KRT82 encodes a hair-specific type II keratin exclusively expressed in the hair shaft cuticle during the anagen (growth) phase 1. As a structural protein, KRT82 is a critical component of intermediate filaments that maintain hair shaft integrity and anchoring within the follicle 2. KRT82 interacts with other keratins, particularly KRT32, to form functional intermediate filament networks essential for proper hair structure 2. Rare damaging variants in KRT82 are significantly associated with alopecia areata (6.01% of cases, p=2.18E-07), an autoimmune hair loss disorder 1. KRT82 expression is decreased in alopecia areata patient skin and hair follicles, correlating with elevated perifollicular CD8+ immune infiltrates, suggesting disrupted hair shaft integrity triggers autoimmune attacks 1. Additionally, KRT82 variants have been identified in keratoconus, a corneal ectasia disease 3, and differential KRT82 expression occurs in laryngeal cells exposed to pepsin, linking to cancer-associated pathways in reflux disease 4. KRT82 is differentially methylated in Alzheimer's disease and major depressive disorder brains 5. In cashmere goats, KRT82 is among key proteins determining fiber diameter 6. Overall, KRT82 functions as a structural determinant of hair and fiber quality, with pathogenic variants predisposing to multiple hair and epithelial disorders.