A very recent study by Podevain and du Jardin in 2012 found that the most common sequence that regulates expression in commercial GMOs also contains and encodes a significant fragment of a viral gene.
The gene in question is called Gene VI and contains a gene fragment, the promoter, responsible for the regulation of the Cauliflower mosaic virus.
Among the affected commercial crops are some of the most widely grown GMOs, including Roundup Ready soybeans (40-3-2) and MON810 maize. They include the controversial NK603 maize recently reported as causing tumors in rats (Seralini et al. 2012).
This discovery will reignite the controversy surrounding the long term safety of GMOS which was not explored before their mass production and introduction into the commercial food market, and suggests that the focus on mandatory labeling efforts of GMO produce is even more imperative.
Love AJ , C Geri, J Laird, C Carr, BW Yun, GJ Loake et al (2012) Cauliflower mosaic virus Protein P6 Inhibits Signaling Responses to Salicylic Acid and Regulates Innate Immunity. PLoS One. 7(10): e47535.
Richins R, H Scholthof, RJ Shepherd (1987) Sequence of figwort mosaic virus DNA (caulimovirus group). NAR 15: 8451-8466.
Ryabova LA , Pooggin, MH and Hohn, T (2002) Viral strategies of translation initiation: Ribosomal shunt and reinitiation. Progress in Nucleic Acid Research and Molecular Biology 72: 1-39.
Séralini, G-E., E. Clair, R. Mesnage, S. Gress, N. Defarge, M. Malatesta, D. Hennequin, J. Spiroux de Vendômois. 2012. Long term toxicity of a Roundup herbicide and a Roundup-tolerant genetically modified maize. Food Chem. Toxicol.
Takahashi H, K Shimamoto, Y Ehara (1989) Cauliflower mosaic virus gene VI causes growth suppression, development of necrotic spots and expression of defence-related genes in transgenic tobacco plants. Molecular and General Genetics 216:188-194.
Zijlstra C, Schärer-Hernández N, Gal S, Hohn T. Arabidopsis thaliana expressing the cauliflower mosaic virus ORF VI transgene has a late flowering phenotype. Virus Genes 1996; 13:5-17.