Studies on forensic applications of human ribonucleases

虽然在人体体液中有许多核酸溶解酶，但这些酶根本没有在法医学领域中使用。因此，本研究旨在使这些酶在该领域的应用更加广泛。(1)两种类型的脱氧核糖核酸酶，DNA酶I和II，分别从人尿中纯化，然后详细表征。用等电聚焦和免疫印迹相结合的方法或新设计的酶谱法，可在人尿或血清中检测到至少10种不同的表型。遗传学研究表明，DNA酶I受同一常染色体位点上4个共显性等位基因控制，基因频率分布较好。因此，人类DNA酶I的遗传多态性被认为是一个有用的工具，法医学个体化。接下来，我们发现尿和白细胞DNA酶II活性水平存在遗传多态性：日本研究人群可分为两种不同的类型，高活性和低活性。从家族研究中，DNA酶II。结果表明，该基因型受同一常染色体上的两个等位基因控制，低活力型受一个隐性等位基因控制。(2)我们成功地从人红细胞、脾和肾中纯化和鉴定了不同的核糖核酸酶（RNasea）。核糖核酸酶的酶学和免疫学性质非常相似，但它们的碳水化合物组成之间存在很大差异。人RNA酶的器官或组织特异性可能是由于其碳水化合物部分的差异。(3)我们用等电聚焦电泳和特异性抗体免疫印迹技术，发现了凝血纤溶系统中的一个因子--人蛋白C抑制物（Protein C Inhibitor）的遗传多态性。

Although there are many nucleolytic enzymes in human body fluids, these enzymes have not been used in the field of forensic sciences at all. So, this study was designed in order to make a wider variety of applications of these enzymes in this field. (1) Two types of deoxyribonuclease, DNases I and II, were purified separately from human urine, and then characterized in detail. By means of the combined technique of isoelectric focusing and immunoblotting or the newly devised zymogram method, at least ten distinct phenotypes could be detected in human urinary or serum DNaseI. From the genetic surveys, it has been known that DNase I was controlled by four codominant alleles at a single autosomal locus with the favorable distribution of its gene frequencies. Therefore, the genetic polymorphism of human DNase I was found to be useful as an effective tool for forensic individualization. Next, we discovered the existence of genetic polymorphism in the activity levels of urinary and leukocytic DNase IIs : the Japanese study population could be classified into two distinct types, high-activity and low-activity. From the family study, DNaseII. was found to be controlled by two alleles at a single autosomal locus the low activity type was due to an recessive allele. (2) We succeeded in purification and characterization of different sibonucleases (RNasea) from human erythrocytes, spleen and kidney. The enzymological and immunological properties of the RNases were very similar but there was a wide difference among their carbohydrate compositions. The organ- or tissue-specificities of human RNases may be due to the differences in their carbohydrate moieties. (3) We discovered the existence of genetic polymorphism in human protein C inhibitor, a factor in the system of blood coagulation and fibrinolysis, using isoelectric focusing electrophoresis and immunoblotting with specific antibodies.