Mismatch analysis of individual identity alignments from STRtyper-21G DNA-typing database
10.13618/j.issn.1001-5728.2025.04.009
- VernacularTitle:STRtyper-21G分型数据库同一性比对容差分析
- Author:
Jiahui SONG
1
;
Zhenping LIU
;
Xiaoxia ZHANG
;
Jingkai YANG
;
Xudong LV
;
Qiannan XU
;
Xiandun ZHAI
Author Information
1. 河南科技大学基础医学与法医学院,河南洛阳 471000
- Publication Type:Journal Article
- Keywords:
Forensic genetics;
STRtyper-21G kit;
Mismatch analysis;
Allele dropout
- From:
Chinese Journal of Forensic Medicine
2025;40(4):434-437
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the loci in the STRtyper-21G kit that are prone to tolerance mismatches when compared with the GlobalFilerTM kit and the PowerPlex? 21 kit,and to analyze the underlying causes.Methods A total of 5,870 database comparison reports involving STRtyper-21G profiles and other autosomal STR kits were examined for identity alignment.Samples showing mismatched loci were re-tested using the STRtyper-21G,GlobalFilerTM,and PowerPlex? 21 kits.For loci with mismatches,primers were redesigned and sequencing was performed.Results Eight mismatched samples(8/5 870)were identified,involving the loci D18S51,D8S1179,and D2S1338.Sequencing revealed that the allele dropout at D18S51 was due to a G→A mutation at the 79th base upstream of the core sequence;at D8S1179,a C→A mutation at the 4th base upstream;and at D2S1338,a C→T mutation at the 22nd base downstream.Conclusion All mismatches were attributable to mutations in primer binding regions.These findings provide reference for interpreting mismatch results in the STRtyper-21G database.When mismatches occur at these loci and the profiles are homozygous,exclusion conclusions should be made with caution.
