Our modestly high-throughput gene expression study and data analysis using a hierarchical clustering algorithm have allowed us to investigate the correlation between tissues and glycosyltransferase gene expression. Similar patterns of glycosyltransferase gene expression were observed in functionally- and anatomically-related tissues. All but one of the sexually-related tissues formed a cluster in a tissue dendrogram, suggesting the involvement of sex hormones in the transcriptional control of many glycosyltransferase genes. Once established, the SM RT-PCR is cost-effective and time-efficient, and requires small amounts of RNA as a template. It is especially useful for the simultaneous analyses of multiple samples. Because of its simple design, the SM RT-PCR may offer an easy alternative in studying the expression of many other families of genes, as well as groups of related/unrelated genes in various biological phenomena.