THE SRY-RELATED GENE SOX9 IS EXPRESSED DURING CHONDROGENESIS IN MOUSEEMBRYOS

Mutations in the human SRY-related gene, SOX9, located on chromosome 1 7, have recently been associated with the sex reversal and skeletal dy smorphology syndrome, campomelic dysplasia. In order to clarify the ro le of this gene in skeletal development, we have studied the expressio n of mouse Sox9 during embryogenesis. Sox9 is expressed predominantly in mesenchymal condensations throughout the embryo before and during t he deposition of cartilage, consistent with a primary role in skeletal formation. Interspecific backcross mapping has localized mouse Sox9 t o distal chromosome 11. The expression pattern and chromosomal locatio n of Sox9 suggest that it may be the gene defective in the mouse skele tal mutant. Tail-short, a potential animal model for campomelic dyspla sia.