Faculty of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510089, China.
Fa Yi Xue Za Zhi. 2023 Jun 25;39(3):247-253. doi: 10.12116/j.issn.1004-5619.2023.530203.
To study the detection efficiency of trio full sibling with another known full sibling reference added under different number of autosomal STR typing systems.
Based on 43 detection systems consisting of 13 to 55 representative autosomal STR loci, 10 000 true families (full sibling group) and 10 000 false families (unrelated individual group) were randomly simulated. The full sibling index (FSI) was calculated based on the method of family reconstruction. The cumulative sibling relationship index (CFSI) of 0.000 1 and 10 000 were used as the evaluation thresholds, and the detection efficiency parameters were calculated and compared with the identification of the duo full sibling testing.
With the increasing number of STR loci, the error rate and inability of judgement rate gradually decreased; the sensitivity, specificity, correct rate of judgment and other parameters gradually increased, and the system efficiency gradually improved. Under the same detection system, trio full sibling testing showed higher sensitivity, specificity, system efficiency and lower inability of judgement rate compared with duo full sibling testing. When the system efficiency was higher than 0.85 and inability of judgement rate was less than 0.01%, at least 20 STRs should be detected for trio full sibling testing, which was less than 29 STRs required by duo full sibling testing.
The detection efficiency of trio full sibling testing is superior to that of duo full sibling testing with the same detection system, which is an effective identification scheme for laboratories with inadequate detection systems or for materials with limited conditions.
研究在添加另一个已知全同胞参考的情况下，不同常染色体 STR 分型系统对三同胞全同胞的检测效率。
基于包含 13 至 55 个代表性常染色体 STR 基因座的 43 个检测系统，随机模拟了 10000 个真实家庭（全同胞组）和 10000 个虚假家庭（无关个体组）。基于家系重建方法计算全同胞指数（FSI）。以累积同胞关系指数（CFSI）为 0.0001 和 10000 作为评价阈值，计算并比较检测效率参数与双全同胞检测的鉴定。
随着 STR 基因座数量的增加，错误率和无法判断率逐渐降低；灵敏度、特异性、判断正确率等参数逐渐升高，系统效率逐渐提高。在相同的检测系统下，三同胞全同胞检测的灵敏度、特异性、系统效率更高，无法判断的比率更低，与双全同胞检测相比。当系统效率高于 0.85，无法判断的比率小于 0.01%时，三同胞全同胞检测至少需要检测 20 个 STR，比双全同胞检测所需的 29 个 STR 要少。
在相同的检测系统下，三同胞全同胞检测的检测效率优于双同胞全同胞检测，这是实验室检测系统不足或材料条件有限时的有效鉴定方案。
