Generation of Fertile Cloned Rats by Regulating Oocyte Activation

Abstract

The rat is a reference animal model for physio-logical studies and for the analysis of multigenic human diseases such as hypertension, diabetes, and neurological disorders (1). Genetic manipu-lation in the rat is hampered by the lack of suitable technologies such as embryonic stem cells (ES), which are routinely used to generate targeted mutations in the mouse. Cloning through somatic cell nuclear transfer (SCNT) is a potential alternative approach in species for which ES technologies are unavailable. Howev-er, all previous efforts to clone rats have been unsuccessful, with developmen-tal arrest at implantation stage [(2) and references therein].