RT-PCR analysis of ZIC1--5 expression in normal tissue and brain tumor tissue. (A) Representative photographs of agarose gels showing RT-PCR products. (B) Relative amounts of ZIC transcripts. The transcript amounts have been normalized to β actin (ACTB) so that the value for the whole brain equals 1.0. Each bar indicates the mean of three independent RT-PCR analyses. Error bars indicate the standard error of the mean. Note that the graphs in (B) indicate the relative transcript amount to those of brain. The relative abundance among the five ZIC transcripts may be partly represented by the difference in the band intensity in (A) together with the PCR cycle and product size differences (See Methods).