中文摘要：

目的探索建立体外STR滑脱模型，研究STR滑脱产生的影响因素，探讨STR的发生机制。方法首先通过全基因组扩增技术一简并寡核苷酸引物PCR（Degenerate oligonueleotide-primedPCR，DOP）对模板DNA样本进行扩增放大，然后以其产物作为后续STR分析的模板，对以上实验过程中的一系列实验条件进行控制．观察滑脱现象的产生情况。结果初步建立了STR的滑脱模型，观察到了STR滑脱现象的发生。结论STR的发生是一系列综合因素作用的结果。DNA模板用量、MgCl2的浓度、DNA聚舍酶的性质、样本以及STR的基序组成等因素均可能参与了这一过程。

英文摘要：

Objective To construct STR slippage model and study factors involved in this procedure. Methods DNA samples were amplified with the technology of Degenerate oligonucleotideprimed PCR ,then their prod- ucts were taken as later DNA template and their STR genotype were analyzed by optimizing several factors. Re- suits STR slippage model was constructed. Conclusion Several factors were involved in the produce of STR slippage, such as amount of modulate DNA, concentration of MgC12, property of DNA polymerase, motif sequence of STR loci, sample, etc.