Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học Critical Care giúp cho các bạn có thêm kiến thức về ngành y học đề tài: Circular reasoning rather than cyclic expression. | Correspondence Circular reasoning rather than cyclic expression Lars Juhl Jensen Ulrik de Lichtenberg Thomas Skot Jensen Soren Brunak and Peer Bork A response to Combined analysis reveals a core set of cycling genes by Y Lu S Mahony PV Benos R Rosenfeld I Simon LL Breeden and Z Bar-Joseph. Genome Biol 2007 8 R146. Addresses European Molecular Biology Laboratory D-69117 Heidelberg Germany. Novo Nordisk Foundation Center for Protein Research University of Copenhagen DK-2200 Copenhagen N Denmark. LEO Pharma DK-2750 Ballerup Denmark. Center for Biological Sequence Analysis Technical University of Denmark DK-2800 Lyngby Denmark. Max-Delbruck-Centre for Molecular Medicine D-13092 Berlin Germany. These authors contributed equally to this work. Correspondence Peer Bork. Email bork@ Published 23 June 2008 Genome Biology 2008 9 403 doi gb-2008-9-6-403 The electronic version of this article is the complete one and can be found online at http 2008 9 6 403 2008 BioMed Central Ltd Transcriptome analyses have identified hundreds of genes that are periodically expressed during the mitotic cell cycle in each of four distantly related eukaryotes budding yeast 1-3 fission yeast 4-6 human 7 and Arabidopsis thaliana 8 . In a paper published in Genome Biology Lu and co-workers 9 challenge the results of earlier comparative studies 4 10-15 by claiming that cell-cycle-regulated transcription is much more conserved at the level of individual genes than previously thought. However we question the validity of their analysis as it relies on circular reasoning allows evidence from homologous genes to overrule experimental evidence from a gene itself assesses conservation on the basis of homology rather than orthology and equates cellcycle function with cell-cycle regulation. Why is the argument circular Previous global studies of cell-cycle-regulated expression analyzed the microarray data from each organism individually and then used orthology relationships .
