Achondroplasia, Severe, with Developmental Delay and Acanthosis Nigricans, also known as saddan, is related to achondroplasia and hypochondroplasia, and has symptoms including seizures An important gene associated with Achondroplasia, Severe, with Developmental Delay and Acanthosis Nigricans is FGFR3 (Fibroblast Growth Factor Receptor 3), and among its related pathways/superpathways are Infectious disease and ERK Signaling. The drugs Hormones and Hormone Antagonists have been mentioned in the context of this disorder. Affiliated tissues include skin and brain, and related phenotypes are intellectual disability, severe and aplasia/hypoplasia of the mandible