IL36RN mutations in generalized pustular psoriasis: just the tip of the iceberg?

As IL36RN mutations are a cause of generalized pustular psoriasis (GPP), three recent investigations attempted to correlate the IL36RN genotype with GPP clinical presentations. These studies found that IL36RN mutations account for only a fraction of GPP cases presenting with concomitant psoriasis vulgaris (PV; common or typical psoriasis). Pathogenic alleles were also found in control populations, indicating that environmental triggers and/or modifier genes may contribute to the disease.