The transgene insertion contains the following elements: ~1235 bp sequence from ~4.5 kb downstream of Atoh1 coding region that comprises the last 278 bp of subregion A and the entire subregion B of enhancer Rr387 or E0, Hbb basal promoter, the beta-galactosidase reporter gene, and SV40 ploy(A) signal sequences. (J:60854)