For sensitive and accurate gene expression analysis, normalization of gene expression data against housekeeping genes is required. There are conventional housekeeping gene (e.g. ACT) that primarily function as an internal control of transcription. In this study, we performed an in silico analysis of 278 rice gene expression samples (GSM) in order to identify the gene that is most consistently expressed. Based on this analysis, we identified novel candidate housekeeping genes that displayed improved stability among the cross experimental conditions. Furthermore four of the most conventional housekeeping genes were included in our 30 other housekeeping genes among the most stable genes. Therefore, these 30 genes can he used to normalize transcription results in gene expression studies on rice at a broad range of experimental conditions.
To evaluate the human risk of long-term intake of genetically modified (GM) rice, we carried out RT-PCR of housekeeping genes. Housekeeping genes, which show highly uniform expression in living organisms during various stages of development and under different environmental conditions, were normalized by RT-PCR. We assessed the expression of 10 common housekeeping genes (18s rRNA, 25S rRNA, UBC, UBQ5, UBQ10, ACT11, GAPDH, eEF-, -TUB, GAPDH, -actin, B2m, G6pd2, Gyk, Gus, Hprt, Cyclophlin A, Tfrc, -tubulin and RPL13A) in the liver, stomach, small intestine, large intestine, kidney and spleen of mice fed GM or non-GM rice. We found no significant differences in the expression of housekeeping genes between the two groups of mice.