AIM:Human hepatitis B virus enhancer Ⅱ B1 binding factor(hBIF) was cloned and characterized as a novel member ofthe Ftz-F1 (NR5A) nuclear receptor subfamily.Althoughprogresses have recently been made,its biological functionremains largely unidentified.The aim of this study was toestablish an hBIF transgenic mouse model to promote thefunctional study of hBIF.METHODS:Transgene fragments were microinjected intofertilized eggs of mice.The manipulated embryos weretransferred into the oviducts of pseudopregnant female mice.The offsprings were identified by PCR and Southern blotanalysis.Transgene expression was analyzed with RT-PCRand Western blot analysis.Transgenic founder mice wereused to establish transgenic mouse lineages.The F1 and F2mice were identified by PCR analysis.RESULTS:Seven mice were identified as carrying copiesof transgene.RT-PCR and Western blotting results showedthat the transgene was expressed in heart,liver,lung,kidneyand stomach in one of the transgenic mouse lineages.Genetic analysis of the transgenic mice demonstrated thatthe transgene was integrated into the chromosome at asingle site,and was transmitted stably.CONCLUSION:In this study we established an hBIFtransgenic mouse model,which will facilitate the investigationof the biological function of hBIF in vivo. AIM: Human hepatitis B virus enhancer II B1 binding factor (hBIF) was cloned and characterized as a novel member of the Ftz-F1 (NR5A) nuclear receptor subfamily. Although there are recently been made, its biological function remains largely unidentified. The aim of this study was to test ablish an hBIF transgenic mouse model to promote the functional study of hBIF.METHODS: Transgene fragments were microinjected intofertilized eggs of mice manipulated embryos were transferred into the oviducts of pseudopregnant female mice. the offsprings were identified by PCR and Southern blot analysis. Transgene expression was analyzed with RT-PCR and Western blot analysis. Transgenic founder mice were used to establish transgenic mouse lineages. F1 and F2 mice were identified by PCR analysis. RESULTS: Seven mice were identified as carrying copies of transgene. RT-PCR and Western blotting showed that the transgene was expressed in heart, liver, lung, kidney and stomach in one of the of transgenic mouse lineages . Genetic analysis of the transgenic mice prototype that the transgene was integrated into the chromosome at asingle site, and was transmitted stably. CONCLUSION: In this study we established an hBIF transgenic mouse model, which will facilitate the investigation of the biological function of hBIF in vivo.