An inducible Mx1 promoter and a 762 bp DNA fragment containing the coding region of human IL11 was used for the transgene. The Mx1 promoter was included for transgene induction by interferon alpha/beta. Since the transgenic animals constitutively expressed human IL11, interferon induction was not implemented. The 3' untranslated region of the transgene contains exons, introns, and polyadenylation sequences from human GH. Transgene expression is constitutively active in several tissues examined by RT-PCR. Furthermore, Northern blot analysis detected transgene expression in the long bone of transgenic animals.