In the latter study, the effect of three polymorphisms in IL-1β gene, rs16944 IL-1β (−511C/T), rs1143627 IL-1β (−31 T/C), and rs1143634 IL-1β (+3,954 T/C), on the severity and occurrence of FMF was also assessed (26). This evidence concerns the gene IL1B and familial Mediterranean fever.