The effect of dietary whole soybeans on rats was analyzed in the level of gene expression using DNA microarray. As soybean content increased in diet, lipid levels in serum and liver were generally lowered. To remove unwanted variation in mRNA expression signals to enable a compatible comparison across different experiments, the DNA microarray data was normalized in accordance with three-parameter log-normal distribution. DNA microarray analyses elucidated that hepatic transcriptome was globally

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... altered depending on the amount of soybean in diets. Among various biological functions, soybean was found to specifically affect transcriptomes involved in lipid/fatty acid biosynthesis in liver. mRNA expressions of these lipogenic genes were lowered with increased amount of soybean in diet. By comparing DNA microarray data across multiple experiments, it was revealed the comprehensive functionality of soybean was correlated with that of freeze-dried tofu. Thus, DNA microarray provides powerful information for understanding the food functionality when those gene expression data is handled properly.