Lykken D T
Behav Genet. 1978 Sep;8(5):437-73. doi: 10.1007/BF01067939.
Uniovular and diovular twin pairs can be classified with at least 90% accuracy by careful questioning or by ratings by observers of similarity in appearance, eye color, ear conformation, and the like. This article outlines the methods required for highly accurate zygosity diagnosis using blood typing, fingerprints, and anthropometry. The logic behind the use of discrete Mendelian phenotypes is explained and tables are provided which give the odds against a dizygotic twin pair showing concordance on eight blood group systems, four serum proteins, and six red blood cell enzymes. These tables are suitable for use with American twins of European ancestry; the method of generating such tables is explained so that similar tables based on different gene frequency estimates or for additional genetic markers can be easily constructed. The logic behind the use of metric, polygenic traits in zygosity diagnosis is also presented, together with tables giving the odds against a dizygotic twin pair showing various degrees of similarity in ponderal index, in cephalic index, and in Slater's Z score, a measure of fingerprint similarity. Taken together, the 18 serological markers should misclassify dizygotic twins as monozygotic fewer than two times in 1000. With the three anthropometric variables, this average probability of misclassification drops about 1 order of magnitude.
通过仔细询问或由观察者对外观、眼睛颜色、耳朵形态等相似性进行评分，同卵和异卵双胞胎对的分类准确率至少可达90%。本文概述了使用血型、指纹和人体测量学进行高精度合子型诊断所需的方法。解释了使用离散孟德尔表型的逻辑，并提供了表格，这些表格给出了异卵双胞胎对在八种血型系统、四种血清蛋白和六种红细胞酶上表现一致的概率。这些表格适用于欧洲血统的美国双胞胎；解释了生成此类表格的方法，以便可以轻松构建基于不同基因频率估计或用于其他遗传标记的类似表格。还介绍了在合子型诊断中使用计量多基因性状的逻辑，以及给出异卵双胞胎对在体重指数、头指数和斯莱特Z分数（一种指纹相似性度量）上表现出不同程度相似性的概率的表格。综合来看，18种血清学标记将异卵双胞胎误分类为同卵双胞胎的次数应少于千分之二。对于三个人体测量变量，这种误分类的平均概率下降约1个数量级。
