法庭科学微单倍型等位基因的数字化命名法  

Numeral Nomenclature Proposed for Microhaplotype Alleles to Exert Effi cient Forensic Applications

作　　者：宋娇娇 张驰 康克莱 陈青峰 季安全 叶健 王乐 SONG Jiaojiao;ZHANG Chi;KANG Kelai;CHEN Qingfeng;JI Anquan;YE Jian;WANG Le(National Engineering Laboratory for Forensic Science,MPS’Key Laboratory of Forensic Genetics,Institute of Forensic Science,Ministry of Public Security(MPS),Beijing 100038,China)

机构地区：[1]公安部鉴定中心,现场物证溯源技术国家工程实验室,法医遗传学公安部重点实验室,北京100038

出　　处：《刑事技术》2022年第6期647-651,共5页Forensic Science and Technology

基　　金：国家自然科学基金(81971797);国家重点研发计划(2017YFC0803503);公安部技术研究计划重点项目(2017JSYJA05)。

摘　　要：微单倍型是一种新型法医遗传学分子标记,可用于个体识别、祖先推断和混合样本DNA的检验。虽然现已有微单倍型基因座的标准命名方法,但简明的微单倍型等位基因命名规则尚未见到。微单倍型遗传标记相对于单核苷酸多态性(single nucleotide polymorphism,SNP)的优势在于其多等位基因。一般来说,微单倍型基因座包含的SNP数目越多,其有效等位基因数(effective number of alleles,Ae)和信息含量(informativeness,In)就倾向于越高。这些基因座更适宜于法庭科学应用,因其复杂的等位基因更能满足应用需求。因此,为更便于应用,我们建议使用阿拉伯数字命名微单倍型等位基因。具体规则如下:以人类基因组正链作为比对微单倍型,GRCh38作为参考序列。将组成微单倍型的SNP根据它们在人类基因组中的物理位置进行排序,dbSNP数据库中的参考等位基因则作为这些SNP可能出现的备选基因型。先按照参考等位基因列出所有可能出现的微单倍型等位基因,然后按照字母表顺序排序,并从1开始以连续正整数依次命名排序后的等位基因。稀有的微单倍型等位基因仍然用SNP分型的组合命名,列在基因座内所有用数字命名的等位基因之后。本文使用9947A、2800M和两份志愿者DNA制备了1∶2∶4∶8比例的DNA混合物,对单一来源样本和混合物进行微单倍型测序、数据分析,并对等位基因进行基因型组合命名和数字化命名两种方式的对比展示。本文建议的数字化命名法其优势在于:首先,这种命名法使得微单倍型的法庭科学应用更便捷,可避免使用SNP分型组合的复杂命名方式,在混合DNA分析中优势尤其显著。其次,在每个微单倍型基因座内部,可以按照阿拉伯数字的顺序排列等位基因,从而能为微单倍型数据的展示和交流提供统一的等位基因排序方式。第三,数字化的等位基因命名方式更易为法医DNA技术人员Microhaplotypes,an emerging type of forensic genetic marker,have been being used for individual identifi cation,ancestry inference and mixture deconvolution as they were incessantly explored and developed.Nevertheless,the concise microhaplotype allelic names have not yet been suggested although there are standardized nomenclatures that were proposed for microhaplotype loci.Here,a proposal was put forward for discussion about microhaplotype alleles being designated with Arabic numerals.For a microhaplotype consisted of single nucleotide polymorphisms(SNPs),the SNPs are locally ordered with their positions in human genome,and have the relevant RefSNP alleles in the dbSNP database be accepted as their possible genotypes.Microhaplotype alleles are allowed to list in every possible combination of the RefSNP alleles before they are arranged in alphabetical order.The ordered alleles are subsequently named with consecutive positive integers starting from 1.Such a nomenclature would be convenient for forensic applications,especially the mixture deconvolution,capable of being enrolled into the software for forensic genetic calculations including PowerStats,Arlequin and STRUCTURE.

关 键 词：法医DNA 微单倍型 等位基因 命名规则 

分 类 号：DF795.2[医药卫生—法医学]