中文摘要：

讨论了L1在人类染色体中的分布密度与染色体长度以及L1的密度与基因密度之间的关系．发现在大多数染色体上L1的密度和染色体的长度表现为正相关，而L1的密度和染色体中基因的密度表现为负相关；对人类L1的5’UTR进行了详细的研究后，发现在L1元件的5’UTR部分含有许多转录因子结合位点．对基因的转录起始位点上游进行统计分析，发现其中含有大量的L1序列．通过对人类的EST数据库进行BLAST分析，新发现了51条和人类L15’UTR相似性较高的EST片断，根据它们分布的组织特异性，说明L1元件可能调控与发育过程有关的基因的表达；最后应用多样性增量的方法对人类和大鼠的L1 5＇UTR进行了区分，得到了较好的预测结果，说明大部分L1的5’UTR的调控作用是人类特有的．

英文摘要：

The relationship between the L1 density and the chromosome length as well as the relationship between the L1 density and the gene density on each human chromosome are discussed. On most human chromosomes, L1 density exhibits positive correlation with the chromosome length and exhibits negative correlation with gene density. Many transcription factor binding motifs are found in the human L1 5＇UTR region for the first time. Through the statistical analysis on the upstream region of gene transcription start site, many L1 sequences are found in this region. By using the BLAST program,51 pieces of tissue specificity EST segments with high similarity to L1 5＇ UTR are found. Finally L1 5＇UTR of the human and the rat is successfully distinguished by use of the algorithm based on the increment of diversity.