基因进化的研究和重构通常是在序列水平上进行的，包括比对它们的遗传序列或蛋白序列。而对基因外显子/内含子结构的分析能够提供更多有价值的信息，比如绘制更为可靠的系统发生图谱，或更精确地阐明内含子的进化。为此，本文设计了相应的Perl脚本程序来提取、比较和搜索基因说明文档中CDS..join特征域的Exon/Intron结构。通过该方法，可构建相关物种的Exon/Intron数据库（EID），其主要内容包括内含子的相位，Exon或Intron的数量、大小，剪接位点的模式以及选择性剪接（Alternative splicing, AS）的相关信息。
The evolution of genes is usually studied and reconstructed at the sequence level, by comparing and aligning their genomic, transcript or protein sequences. However, including the exon-intron structure of genes in the analysis can provide further and useful information, for example to draw reliable phylogenetic relationships left unsolved by traditional sequence-based evolutionary studies, or to shed further light on patterns of intron gain and loss. So, in this work we present the Perl program designed to retrieve, compare and search for the exon-intron structure in CDS..join features of existing gene annotations. By this means, we can construct an Exon-Intron database (EID), including the phase of intron, the number/size of exon and intron, the pattern of splicing site and the information of alternative splicing (AS).