Although the amount of information regarding the role of growth factors and cytokines as inducers and mediators of MSC differentiation continues to increase, little is known about the gene expression profiling of MSC chondrogenic differentiation. In this study, we employed ABI GeneChips (representing > 30,000 genes) to identify genes differentially expressed during BM-MSC chondrogenesis. ABI is introduced technology based on nylonspotted 60 mer oligonucleotides, that uses on oligomers to detect each gene for most genes, chemiluminescence to measure gene expression levels, and fluorescence to grid to normalize and identify microarray features. The ABI gene list was compiled from information in public and Celera databases (6) . This study was designed to identify differential gene expression profiles and novel genes that might be involved in BM-MSC chondrogenesis. 