Figure 1

Col2a1-CreER^T2; Ihh^fl/flmice exhibit normal phenotype before induction. (A) Insertion of loxP restriction enzyme site in the Indian hedgehog (Ihh) allele was confirmed by PCR. Lane 1: heterozygous Ihh^fl/fl (382 bp and 484 bp), lane 2: homozygous Ihh^fl/fl (382 bp), lane 3: wild type (WT) (484 bp), lane 4: 50-bp DNA marker and lane 5: Cre-recombinase (328 bp). (B) X-rays and Safranin O–stained images show normal growth plate and proteoglycan staining in WT mice (a) and mutant mice (b) at 2 months of age without deletion of Ihh.