精液与阴道液混合斑的个人识别是法医学鉴定中的难点之一，选择分离精子成分并对其遗传特征进行鉴定是目前的重要手段。然而，现今的研究方法还不能达到理想和高效的分离混合斑中精子的目的。人类受精过程是以卵母细胞外卵膜糖蛋白（ZP）与精子特异结合为先决条件的，人类存在着四种ZP，分别作为起始与次级受体与精子以配体-受体方式特异性结合，诱发顶体反应等生理功能。本研究将利用ZP与精子特异性识别结合的生物学特性，重组克隆四种ZP基因并进行过表达；纯化含载体标签与ZP的融合蛋白，或酶解后纯化ZP蛋白；融合的与单纯的ZP与精子及不同条件下保存的混合斑中精子进行结合试验；抗标签抗体、吸附生物素化ZP的链霉亲和素或抗ZP抗体交联的琼脂糖珠特异地结合融合蛋白或ZP蛋白，分离纯化精子；得到的精子进行DNA多态性标记分析。同时也将该方法应用于法医学实际案例中。该方法的准确实施将为法医学混合斑中精子细胞分离开拓一个新思路。

Personal identification for mixture stain with sperms and vaginal fluid is one of aporias in forensic medicine. At present, it has still been a main way to isolate sperms from mixture stain and subsequently detect its genetic polymorphism. However, a perfect and high-efficiency method for isolation of sperms from mixture stain has not been established yet. It is a prerequisite that the spermatozoa bind to the zona pellucida (ZP) matrix surrounding the oocyte during human fertilization. The ZP matrix in human is composed of four glycoproteins, which act as primary and secondary receptors binding spermatozoa to form specific and high-efficiency ligand-receptor binding complex. Next, the binding complex may induce the acrosome reaction in the ZP-bound spermatozoon and result in following physiological action. In this study, we shall apply the biological feature for specific recognization and binding to make the recombinants with each ZP gene and different vectors, to purify the fusion proteins and ZP alone as well as the fusion proteins digested with enzyme after the recombinants are expressed, to perform a binding assay with the recombinant ZP and spermatozoa both from seminal fluid and mixture stain kept at different conditions, and to specifically adhere ZP-spermatozoa complexes on Sepharose resins cross-linked with anti-tag antibodies, streptavidin or anti-ZP antibodies. Finally, we shall carry out an examination of DNA polymorphism based on short tandem repeat (STR) from isolated spermatozoa samples. In addition, we shall also use the de novo invention to caseworks in forensic medicine. Undoubtedly, the method implemented with optimization and inerrability will open up a novel thought for isolation of spermatozoa from mixture stain in forensic medicine.