Li Ran, Zang Yu, Liu Jiajun, Wu Enlin, Wu Riga, Sun Hongyu
Medical College, Jiaying University, Meizhou 514031, China.
Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510080, China.
Genes (Basel). 2025 Apr 15;16(4):455. doi: 10.3390/genes16040455.
BACKGROUND/OBJECTIVES: Kinship inference is commonly adopted in various forensic applications, but previous studies have often lacked precision.
In this study, a new method for the nomenclature of kinship types, i.e., kinship chain (KC), was proposed, and then, six types of identity by state (IBS) scores were calculated for simulated and real families using four types of markers. Finally, several Bayesian network (BN)-based classifiers were constructed to investigate the efficiency of the kinship inference.
A total of 7, 22, 58, and 3 KCs were obtained for common first-, second-, and third-degree relatives and unrelated pairs, respectively. High accuracies could be achieved in distinguishing between related and unrelated pairs after combining the four types of genetic markers, with an accuracy of >99.99% for all 7 KCs of first-degree relationships and ~99% for 14 out of 22 KCs of second-degree relatives. When comparing relationships of the same degree, the accuracies were 99.28%, 42.31%, and 15.82% for first-, second-, and third-degree relationships, respectively. When it came to differentiating unspecific relationships, the overall accuracy was over 80%. All the results were validated on real family data.
With the new nomenclature method of kinship types and the combination of autosomal and non-autosomal genetic markers, kinship inference can be realized with high accuracy and precision, which will be helpful in complex forensic cases, such as the identification of mass disaster victims.
背景/目的：亲缘关系推断在各种法医应用中普遍采用，但以往的研究往往缺乏精确性。
在本研究中，提出了一种新的亲缘关系类型命名方法，即亲缘关系链（KC），然后使用四种类型的标记物为模拟家庭和真实家庭计算六种状态一致性（IBS）得分。最后，构建了几个基于贝叶斯网络（BN）的分类器来研究亲缘关系推断的效率。
分别为常见的一级、二级和三级亲属以及无关个体对获得了7个、22个、58个和3个亲缘关系链。结合四种类型的遗传标记物后，区分相关和无关个体对可获得较高的准确率，一级关系的所有7个亲缘关系链的准确率>99.99%，二级亲属的22个亲缘关系链中有14个的准确率约为99%。在比较相同程度的关系时，一级、二级和三级关系的准确率分别为99.28%、42.31%和15.82%。在区分非特定关系时，总体准确率超过80%。所有结果均在真实家庭数据上得到验证。
采用新的亲缘关系类型命名方法并结合常染色体和非常染色体遗传标记物，可以高精度地实现亲缘关系推断，这将有助于处理复杂的法医案件，如大规模灾难受害者的身份识别。
