The transgenic construct contains a 9kb sequence of the 5' portion of the mouse Hlxb9 (Mnx1) gene, a 5' splice substrate, an enhanced Green Fluorescent Protein (EGFP) open reading frame, and a bovine growth hormome polyadenylation site sequence. Line 1 contains 10 to 11 tandem copies of the transgene. The expression pattern of this transgene is the same as that for the endogenous gene from which the promoter is derived. (J:88764, J:271391)