ABSTRACT
<p><b>OBJECTIVE</b>To identify the genes differentially expressed among the steroid-resistant nephrotic syndrome (SRNS), steroid-sensitive nephrotic syndrome (SSNS) and normal children, and understand the molecular mechanism of SRNS.</p><p><b>METHODS</b>Affymetrix microarray technology was used to obtain such a profile. The differentially expressed genes among these groups were identified based on signal-to-noise ratios by GCOS software; real-time PCR analysis was performed to confirm the microarray results.</p><p><b>RESULTS</b>There were 157 genes differentially expressed among these groups. The genes up-regulated both in SRNS and SSNS were involved primarily in ionic transportation, immuno-signal transduction and apoptosis. In particular, CLNS1A gene was down regulated in SRNS but up regulated in SSNS.</p><p><b>CONCLUSION</b>Several differentially expressed genes, such as CLNS1A and HLA-DRB4 were found to be closely related to the pathogenesis of SRNS and SSNS. This DNA microarray analysis has provided some important clue to the molecular mechanism of SRNS.</p>