法医学杂志 ›› 2019, Vol. 35 ›› Issue (2): 205-209.DOI: 10.12116/j.issn.1004-5619.2019.02.014

• 论著 • 上一篇    下一篇

基于NGS-SNP分型和IBS策略进行全同胞关系鉴定

王致远1,2, 王迪佳3, 李燃1, 李海霞1, 汪娜娜1, 孙宏钰1   

  1. 1. 中山大学中山医学院法医学系,广东 广州 510089; 2. 佛山市公安局,广东 佛山 528000; 3. 深圳市公安局龙华分局,广东 深圳 518109
  • 发布日期:2019-04-25 出版日期:2019-04-28
  • 通讯作者: 孙宏钰,女,教授,博士研究生导师,主要从事法医物证学研究;E-mail:sunhongyu2002@163.com
  • 作者简介:王致远(1986—),男,硕士研究生,主要从事法医物证学研究;E-mail:316439357@qq.com
  • 基金资助:
    国家自然科学基金面上资助项目(81671873)

Full Sibling Testing Based on NGS-SNP Genotyping Method and IBS Strategy

WANG Zhi-yuan1,2, WANG Di-jia3, LI Ran1, LI Hai-xia1, WANG Na-na1, SUN Hong-yu2   

  1. 1. Department of Forensic Medicine, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510089, China; 2. Foshan Public Security Bureau, Foshan 528000, Guangdong Province, China; 3. Longhua Branch of Shenzhen Public Security Bureau, Shenzhen 518109, Guangdong Province, China
  • Online:2019-04-25 Published:2019-04-28

摘要: 目的 评估单核苷酸多态性(single nucleotide polymorphism,SNP)分型结合状态一致性(identity by state,IBS)分析策略进行全同胞鉴定的效能。 方法 收集一个四代家系共35个成员的血样,采用Precision ID Identity Panel对90个常染色体SNP进行分型。统计并比较全同胞与其他亲缘关系IBS评分分布的差异,分别采用Fisher判别函数法和阈值法进行各种亲缘关系判定。 结果 基于家系和前期研究,分别获得全同胞、祖孙、叔侄(姨甥)、第一代堂表亲关系共44、30、111、71对以及无关个体1 000对,平均IBS评分分别为148、130、132、124、120。除祖孙与叔侄(姨甥)关系外,其余关系之间的IBS评分差异均有统计学意义(P<0.05)。基于IBS评分建立的Fisher判别函数对于全同胞、祖孙、叔侄(姨甥)、第一代堂表亲关系的错判率分别为1.3%、22.3%、17.0%、38.7%。基于10 000对模拟样本的IBS评分分布,推荐使用t1=128、t2=141作为全同胞判定的IBS阈值(错判率≤0.05%)。 结论 Precision ID Identity Panel包含的90个SNP遗传标记可满足全同胞关系的鉴定要求,基于IBS评分的阈值法的错判率更低,使用更加灵活。

关键词: 法医遗传学, 单核苷酸多态性, 同胞关系, 状态一致性, 下一代测序

Abstract: Objective To evaluate the effectiveness of single nucleotide polymorphism (SNP) genoty-ping in combination with identity by state (IBS) strategy in full sibling testing. Methods Thirty-five blood samples were collected from a four-generation family. Ninety autosomal SNPs were genotyped using Precision ID Identity Panel. The distribution of IBS scores for full siblings and other relationships were calculated and compared. The relationships were determined using Fisher discriminant function and threshold method, respectively. Results Based on family members and previous research, 44, 30, 111, 71 and 1 000 pairs of full siblings (FS), grandparent-grandchild (GG), uncle/aunt-nephew/niece (UN), first cousins (FC) and unrelated individuals (UI) were obtained, respectively. The average IBS scores were 148, 130, 132, 124 and 120, respectively. Except for the GG and UN pairs, the distribution differences among the other relationships had statistical significance (P<0.05). The false rates of Fisher discriminant function to determine relationships were 1.3%, 22.3%, 17.0% and 38.7% for FS, GG, UN and FC, respectively. Based on the simulation data, the thresholds t1=128 and t2=141 were recommended to determine full sibling relationships (the false rate ≤0.05%). Conclusion The 90 SNP genetic markers included in the Precision ID Identity Panel meet the testing requirements for full sibling relationships. The threshold method based on IBS has a relatively lower false rate and is more flexible.

Key words: forensic genetics, single nucleotide polymorphism, sibling relations, identity by state, next generation sequencing