The presence of modified genes resistant to a chemical herbicide Roundup Ready (glyphosate) in commercially available bean curd (tofu) labeled as modified gene-free was examined by the PCR method. Samples were taken from twelve brands of bean curd all available on the market and bought during August and September 2005. For DNA extraction, PCR analysis was conducted from primers based on the disclosed Roundup Ready-resistant expression sequence and soybean lectin expression sequence using a DNeasy Plant Mini Kit produced by Qiagen, and the results were confirmed by electrophoresis. As a result a clear band that appears to derive from modified genes was detected in one brand, and a trace of such a band was detected in two other brands. In an analysis of unsorted ration for livestock carried out for comparison, a clear band that appears to derive from modified genes was detected
