From structure to function for the characterization of ERAP1 active site in Behçet syndrome. A novel polymorphism associated with known gene variations.

•Genotyping of Italian patients with Behçet syndrome showed a novel ERAP1 polymorphism.•The novel p.Phe360Cys SNP is within the Zn-binding region of ERAP1 active site.•The novel SNP is predicted to be damaging (maximun score of deleteriousness).•The SNP could affect the structurally conserved region for the enzymatic function.•The down-regulation of mRNA ERAP1 was recognized in presence of p.Phe360Cys SNP.