AP1S3 and palmoplantar pustulosis: As discussed previously, autoinflammatory variants of generalized and localized pustular psoriasis can result from several pathogenetic pathways, i.e., IL36RN loss-of-function (OMIM no. 605507), CARD14-activating (OMIM no. 602723), and AP1S3 loss-of-function (OMIM no. 616106) pathogenic variants.