A bacterial artificial chromosome (BAC) clone (RP23-367A8) containing the full length of mouse retinoic acid gene 8 (Stra8) was used. At the end of Stra8 open reading flame in exon 9, the open reading frame of the enhanced green fluorescent protein (Egfp) gene combined with beta-globin polyA signal site was inserted into RP23-367A8. (J:202057)