In order to identify the molecular mechanisms controlling preadipocyte commitment we derived new sublines of Swiss 3T3 fibroblasts with varying potential for adipogenesis. Swiss 2, Swiss 8, Swiss 9, and Swiss 19 differentiate into fat cells while Swiss 3, Swiss 5, and Swiss 22 have a lower propensity to differentiate into fat cells. The overall goal was to identify genes whose expression in the fibroblast state correlates with the ultimate potential of the cells to undergo adipogenesis Overall design: 4 preadipose fibroblast cell lines (Swiss 2, Swiss 8, Swiss 9, and Swiss 19 in triplicate or duplicate) were compared to 3 non-adipogenic fibroblast cell lines (Swiss 3, Swiss 5, Swiss 22 in triplicate)