DNA polymorphisms and renal disease: a critical appraisal of studies presented at the annual ERA/EDTA and ASN conferences in 2004 and 2005.

Countless studies try to associate single DNA polymorphisms with disease, while there is growing evidence that many of these studies are of flawed design. Based on the Journal of the American Society of Nephrology (JASN) requirements for gene-disease association study quality, the abstracts presented at the two major international nephrology conferences in 2004 and 2005 organized by the European Renal Association/European Dialysis and Transplantation Association (ERA/EDTA) and American Society of Nephrology (ASN) are analysed to show how this problem affects nephrology. Over time, average sample numbers have increased, as have the numbers of abstracts compliant with the JASN requirements. This indicates a potential beneficial effect of the published stricter guidelines on study quality. Alternative options include pre-registration of studies in dedicated databases, secondary assessment of association studies through meta-analysis and participation in network approaches, such as the Human Genome Epidemiology Network (HuGE Net) and the Renal Genome Network.