Burkhardt A
Institut für Humanbiologie, Abteilung Anthropologie, Technischen Universität, Braunschweig.
Anthropol Anz. 1992 Sep;50(3):235-70.
Subject of the present report is an investigation of the heredity of 30 iris characteristics. The material basis of this sample of twins (100 monozygotic and 100 dizygotic pairs), the largest ever taken as a basis for the purpose of iris research, consists of standardized colour photographs of the examined persons' irises and iris-microscopic observations. The pairs of twins are compared to 100 non-related casual pairs in order to render a better estimation of the degree of heredity of the features possible. On every occasion several classes were constituted for the concordance verification. These classes result from the number of the classes of the forms of markedness and present different levels of similarity. The different distribution of the twin pairs and the control pairs on the concordance classes are always examined for their statistical significance, and for each group of pairs a concordance value is computed. The intervals between the concordance values of the monozygotic and dizygotic pairs and the control pairs indicate the degree of heredity of the investigated feature. Taking all the compiled factors and conditions into consideration, an evaluation of the features as heredity features is made. Though a hereditary component can be observed for all iris characteristics, only about a third could be called heredity features. Quantity of pigment and the hitherto undescribed limiting layer folds were evaluated as "very good", whereas pigment colour in the fine analysis, quality of the anterior stroma leaf, frequency of iris crypts and iris frill position were judged as "good". Tone of blue, markedness of Woelfflin nodules, quantity and markedness of contractional rings could be evaluated as "moderately good" as to their heredity. On the basis of the prior concordance investigations for each of the 300 pairs, a "similarity index" and a "concordance index" were computed in order to arrive at evidence as to the degree of similarity of the single pairs; i.e. in order to detect the limits of the similarity between non-identical twins and the dissimilarity between identical twins. This concluding investigations lead to the question of the possibility of a diagnosis of genetic identicalness solely on the basis of the comparison of irises.
本报告的主题是对30种虹膜特征的遗传情况进行调查。该双胞胎样本（100对同卵双胞胎和100对异卵双胞胎）是有史以来用于虹膜研究的最大样本，其物质基础包括被检查者虹膜的标准化彩色照片和虹膜显微镜观察结果。将双胞胎与100对无亲属关系的随机配对进行比较，以便更好地估计这些特征的遗传程度。每次都构建几个类别用于一致性验证。这些类别由标记形式的类别数量产生，并呈现出不同程度的相似性。总是会检查双胞胎对和对照对在一致性类别上的不同分布的统计显著性，并为每组配对计算一个一致性值。同卵双胞胎、异卵双胞胎和对照对的一致性值之间的间隔表明了所研究特征的遗传程度。综合考虑所有汇编的因素和条件，对这些特征作为遗传特征进行评估。尽管所有虹膜特征都能观察到遗传成分，但只有大约三分之一可被称为遗传特征。色素量和迄今为止未描述的限制层褶皱被评估为“非常好”，而精细分析中的色素颜色、前基质叶的质量、虹膜隐窝的频率和虹膜褶位置被判定为“好”。蓝色色调、沃尔夫林结节的明显程度、收缩环的数量和明显程度在遗传方面可被评估为“中等好”。基于对300对中的每一对之前的一致性调查，计算了一个“相似性指数”和一个“一致性指数”，以便获得关于单对之间相似程度的证据；即，以便检测非同卵双胞胎之间的相似极限和同卵双胞胎之间的差异极限。这项总结性调查引发了仅基于虹膜比较进行基因同一性诊断可能性的问题。
