A new set of DIP-SNP markers for detection of unbalanced and degraded DNA mixtures
A new set of DIP-SNP markers for detection of unbalanced and degraded DNA mixtures
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一组新的 DIP™SNP 标记，用于检测不平衡和降解的 DNA 混合物
DOI：
10.1002/elps.201900017
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发表时间：
2019-07-01
期刊：
影响因子：
2.9
通讯作者：
Yun, Keming
中科院分区：
文献类型：
--
作者：
Liu, Jinding;Li, Wenyan;Yun, Keming
法医 DNA 分析过程中经常会遇到不平衡和降解混合物 (UDM)。例如，法医 DNA 单位经常遇到 DNA 混合信号，其中来自犯罪嫌疑人的 DNA 信号被来自受害者的大量 DNA 掩盖或淹没。我们之前的数据提出了一种由删除/插入多态性（DIP）和SNP组成的新型DNA标记，我们将这种新型微单倍型DIP-SNP（DIP和SNP的组合）称为。由于此类标记可以设计得足够短以用于降解的 DNA 扩增，因此我们假设 DIP-SNP 标记适用于 UDM 分型。在这项研究中，我们开发了一套新的带有短扩增子的 DIP-SNP，这是对我们之前开发的系统的补充。针对中国汉族人群中的 20 个 DIP-SNP 建立了多重 PCR 和 SNaPshot 检测。 DIP-SNP 能够检测自制 DNA 混合物中的次要贡献者等位基因，灵敏度为 1:100 至 1:1000，输入 DNA 总量为 1 –10 ng。此外，该系统成功地对降解的 DNA 进行了分型，无论它是来自单一来源还是混合样本。在中国人群中，该系统的平均信息值为0.293，综合信息值为0.998363862。我们的结果表明，DIP-SNP 可作为法医学检测 UDM 的有价值的工具。
Unbalanced and degraded mixtures (UDM) are frequently encountered during forensic DNA analysis. For example, forensic DNA units regularly encounter DNA mixture signal where the DNA signal from the alleged offender is masked or swamped by high quantities of DNA from the victim. Our previous data presented a new kind of DNA markers that composed of a deletion/insertion polymorphism (DIP) and a SNP and we termed this new kind of microhaplotypes DIP‐SNP (combination of DIP and SNP). Since such markers could be designed short enough for degraded DNA amplification, we hypothesized that DIP‐SNP markers are applicable for typing of UDM. In this study, we developed a new set of DIP‐SNPs with short amplicons which were complement to our prior developed system. The multiplex PCR and SNaPshot assay were established for 20 DIP‐SNPs in a Chinese Han population. The DIP‐SNPs were capable of detecting the minor contributor's allele in home‐made DNA mixture with sensitivities from 1:100 to 1:1000 with a total of 1 –10 ng input DNA. Moreover, this system successfully typed the degraded DNA whether it came from the single source or mixture samples. In Chinese population, the system showed an average informative value of 0.293 and combined informative value of 0.998363862. Our results demonstrated that DIP‐SNPs may serve as a valuable tool in detection of UDM in forensic medicine.