"Breakthrough" or delusion?

New results cast doubt upon the stem cells from human testis cultivated in Tübingen. A recent analysis reveals that the data were misinterpreted

A sientist's findings are not considered valid unless they can be independently reproduced by other researchers. Attempts to reproduce the 2008 results of Thomas Skutella and his team of the Centre for Regenerative Biology and Medicine (ZRM) in Tübingen are, however, practically impossible. Furthermore, other stem cell scientists, among them the group of Hans Schöler of the Max Planck Institute for Molecular Biomedicine in Münster (MPI), Germany, have in vain requested a sample of these cells for more than a year. In the online issue of Nature, Hans Schöler’s team and a research group of Martin Zenke of RWTH Aachen University report on their bioinformatics analysis of the microarray data published by Skutella’s group. They have arrived at the conclusion that the “Tübingen cells” are not pluripotent, but are most likely simple connective tissue cells. (Nature online, June 24, 2010)