Abstract: Microarray technology has been applied in a variety of biological and medical research fields.Due to the relative higher costs,some researchers are apt to pooling RNA samples extracted from different subjects onto a single microarray to defray the cost of microarray experiment.The basic assumption of pooling is that the pooling RNA can lessen the diversity between individual subjects.Employing an example in cancer research,the authors analyzed the differential expressed genes between gastric cancer tissues and its corresponding adjacent normal tissues using ten individual RNA and their pooling RNA.The results indicate that there are no significant variances between pooling and individual RNA concerning of the numbers of correct gene,false positive gene and false negative gene based on a statistical approach.So the authors suggest using RNA from individual subject instead of pooling them even if in the primary studies.

Key words: DNA microarray, pooling RNA, individual subject