The protein encoded by this gene is a member of the interleukin 1 cytokine family. This cytokine was shown to specifically inhibit the activation of NF-kappaB induced by interleukin 1 family, member 6 (IL1F6). This gene and eight other interleukin 1 family genes form a cytokine gene cluster on chromosome 2. Two alternatively spliced transcript variants encoding the same protein have been reported.