Kratzer A, Bär W
Institut für Rechtsmedizin, Universität Zürich-Irchel, Zürich.
Ther Umsch. 1997 May;54(5):280-5.
In Switzerland paternity investigations are carried out using DNA analysis only since 1991. DNA patterns are inherited and only with the exception of genetically identical twins they are different in everyone and therefore unique to an individual. Hence DNA-systems are an excellent tool to resolve paternity disputes. DNA polymorphisms used for paternity diagnosis are length polymorphisms of the highly polymorphic VNTR loci [variable number of tandem repeats]. The most frequently applied systems are the DNA single locus systems. In addition to the DNA single locus systems the application of PCR (PCR = polymerase chain reaction) based DNA systems has increased particularly in difficult deficiency cases or in cases where only small evidential samples or partially degraded DNA are available. Normally four independent DNA single probes are used to produce a DNA profile from the mother, the child and the alleged father. A child inherits half the DNA patterns from its mother and the other half from its true biological father. If an alleged father doesn't possess the paternal specific DNA pattern in his DNA profile he is excluded from the paternity. In case of non-exclusion the probability for paternity is calculated according to Essen-Möller. When applying four highly polymorphic DNA single locus systems the biostatistical evaluation leads always to W-values exceeding 99.8% [= required value for positive proof of paternity]. DNA analysis is currently the best available method to achieve such effective conclusions in paternity investigations.
在瑞士,亲子鉴定自1991年起才开始采用DNA分析技术。DNA图谱是可遗传的,除了基因完全相同的双胞胎外,每个人的DNA图谱都是不同的,因此具有个体独特性。所以DNA检测系统是解决亲子关系纠纷的绝佳工具。用于亲子鉴定的DNA多态性是高度多态性VNTR位点(可变串联重复序列)的长度多态性。最常应用的系统是DNA单一位点系统。除了DNA单一位点系统外,基于PCR(PCR=聚合酶链反应)的DNA系统的应用有所增加,特别是在疑难缺失案例或仅有少量证据样本或部分降解DNA的案例中。通常使用四个独立的DNA单探针来生成母亲、孩子和被指控父亲的DNA图谱。孩子从母亲那里继承一半的DNA图谱,从其真正的生物学父亲那里继承另一半。如果被指控的父亲在其DNA图谱中不具备父系特异性DNA图谱,他就会被排除在亲子关系之外。在不能排除的情况下,根据埃森-默勒法计算亲子关系概率。当应用四个高度多态性的DNA单一位点系统时,生物统计学评估得出的W值总是超过99.8%[=亲子鉴定阳性证明的要求值]。目前,DNA分析是在亲子鉴定调查中得出如此有效结论的最佳可用方法。