| First Author | Nii A | Year | 1995 |
| Journal | Am J Pathol | Volume | 147 |
| Issue | 6 | Pages | 1871-82 |
| PubMed ID | 7495310 | Mgi Jnum | J:30149 |
| Mgi Id | MGI:77663 | Citation | Nii A, et al. (1995) Mild osteopetrosis in the microphthalmia-oak ridge mouse. A model for intermediate autosomal recessive osteopetrosis in humans. Am J Pathol 147(6):1871-82 |
| abstractText | Mutations at the mouse microphthalmia (mi) locus affect coat color, eye development, and mast cells. The original allele, mi, also shows severe osteopetrosis. Mice homozygous for the microphthalmia-Oak Ridge (Mior) mutation are white, microphthalmic animals with retarded incisor development. To investigate whether this mutation causes osteopetrosis, we examined skeletal tissues of the Mior mouse. A typical osteopetrotic lesion, accumulation of unresorbed primary spongiosa, was found at the metaphyses of long bones and at the costochondral junctions in Mior/Mior mice from 10 days to 37 days of age, whereas no accumulation was seen at the mid-diaphyses in these bones. The osteopetrotic conditions of Mior/Mior mice increased progressively during the first 5 weeks after birth. However, adult Mior/Mior mice 3 months or older showed improvement of the osteopetrotic condition, although the disease was not completely resolved. Ultrastructurally, osteoclasts of Mior/Mior mice had well developed ruffled borders. These results show that the Mior mutation has milder osteopetrotic changes than the original mi mutation, a surprising observation given that both mutations affect the same functional domain of the mi protein, a basic-Helix-Loop-Helix-Zipper transcription factor. The Mior phenotype resembles the intermediate autosomal recessive osteopetrosis in humans. |
