Pathophysiology: The activation of mutations in the FGFR3 gene is crucial to the pathogenesis of SK, which includes various benign skin disorders; dermatosis papulosa nigra (DPN) is characterized by benign, black papules arising from hyperpigmented keratinocytes in individuals with darker skin tones. The gene discussed is FGFR3; the disease is dermatosis papulosa nigra.