Clinical, genetic, and biochemical findings in two siblings with Papillon-Lefèvre Syndrome.

Background: Papillon-Lefèvre Syndrome (PLS) is an autosomal recessive disease characterized by palmoplantar hyperkeratosis and severe periodontitis affecting both primary and secondary dentitions. Cathepsin C (CTSC) gene mutations are etiologic for PLS. The resultant loss of CTSC function is responsible for the severe periodontal destruction seen clinically.