Microreader™ 23sp ID system was a new STR multiplex system developed for forensic application, but there was a lack of population data in the Chinese Han population. This kit contained 21 non-CODIS STR loci (D6S477, D18S535, D19S253, D15S659, D11S2368, D20S470, D1S1656, D22-GATA198B05, D7S3048, D8S1132, D4S2366, D21S1270, D13S325, D9S925, D3S3045, D14S608, D10S1435, D12S391, D2S1338, D17S1290, D5S2500), one CODIS STR locus (D16S539) and the amelogenin locus. In this study, a population sample in Chengdu Han population was analyzed with the kit. Forensic genetic parameters and probability values of the Hardy–Weinberg equilibrium (HWE) were calculated with software PowerStats v1.2 and Arlequin v3.5. Allele frequencies of the 22 STR loci and further forensic genetic parameters were obtained. The results suggested that Microreader™ 23sp ID system can provide informative polymorphic data for identification and parentage testing in Chinese Han population.
STRs was widely used in paternity test, individual identification and biological anthropology because they can be easily amplified by the polymerase chain reaction (PCR) [
], and its diversity and genetic differentiation of human populations. Nevertheless, there was an absence of genetic information for some countries or areas. In this study, 22 autosomal STR loci in the Chengdu Han population were investigated using the Microreader™ 23sp ID system, to obtain the data of population genetics and determine the genetic variability.
- Butler J.M.
- Hill C.R.
Biology and genetics of new autosomal STR loci useful for forensic DNA analysis.
For. Sci. Rev. 2012; 24: 15
2. Materials and methods
Blood samples were collected from 152 unrelated individuals (109 males and 43 females) of the Han population living in Chengdu, northwest China after informed consent. Genomic DNA was isolated by the salting out extraction method and quantified by the NanoDrop1000 Spectrophotometer (Nano-Drop Technologies, Wilmington, DE, USA). The samples were amplified using the Microreader™ 23sp ID system (Suzhou Microread Genetics, Suzhou, Jiangsu, China), PCR amplification was carried out on a Mastercycler® pro (Eppendorf, Germany) following the manufacturer’s instructions, and amplified products were separated by capillary electrophoresis on a 3130 DNA Genetic Analyzer (Applied Biosystems, USA). Electrophoresis results were analyzed using GeneMapper ID 3.2 software (Applied Biosystems). The experimental procedures were guided in keeping with laboratory internal control standards and kit controls. Forensic statistical parameters were calculated by PowerStats v1.2 software [
], observed heterozygosity, expected heterozygosity and the chi-square test of Hardy–Weinberg equilibrium (HWE) were analyzed with ARLEQUIN version 3.5 software [
- Tereba A.
Tools for analysis of population statistics.
Profiles DNA. 1999; 3: 14-16
- Excoffier L.
- Lischer H.E.L.
Arlequin suite ver 3.5: a new series of programs to perform population genetics analyses under Linux and Windows.
Mol. Ecol. Resour. 2010; 10: 564-567
3. Results and discussion
Allele frequencies and forensic parameters were listed in Table 1. The observed heterozygosity (Ho) ranged from 0.7171 (D10S1435) to 0.8684 (D2S1338) while the expected heterozygosity (He) ranged from 0.7294 (D10S1435) to 0.8733 (D7S3048). The power of discrimination (PD) ranged from 0.8831 (D10S1435) to 0.9627 (D11S2368) and the probability of excluding paternity (PE) ranged from 0.4552 (D10S1435) to 0.7315 (D2S1338). The combined power of discrimination (CPD) in the 22 STR loci was 0.999999999999999999999999996806 and combined probability of matching (CPE) was 3.1943 × 10−27. The value of combined probability of exclusion was 0.99999999975. All of 22 STR loci showed no statistically significant deviation from Hardy–Weinberg equilibrium (HWE). Except D10S1435 (PIC = 0.6860) rest of the 21 STR loci presented high polymorphism (PIC > 0.7), and the most informative locus was D7S3048 (PIC = 0.8566).
Table 1Allele frequencies of the 22 autosomal STR loci and forensic parameters of Chengdu Han population in China (N = 152).
Ho: observed heterozygosity, He: expected heterozygosity, MP: matching probability, PD: power of discrimination, PIC: polymorphism information content, PE: probability of excluding paternity, TPI: Typical Patemity Index, p: p values of the exact test for the Hardy–Weinberg equilibrium.
Our results showed that Microreader™ 23sp ID system could amplify 22 autosomal STR loci (contained 21 non-CODIS STR loci) and one sex-determining locus in a single reaction and it presented extremely high CPD and CPE value in the Chengdu Han population. Based on these we suggest that Microreader™ 23sp ID system could provide informative polymorphic data for identification and parentage testing in Chinese Han population, especially for deficiency cases of paternity test and the presence of STR mutation.
Conflict of interest
The authors would like to thank all volunteers who donated samples. This work was supported by the National Natural Science Foundation of China (81273349, 81330073).
- Biology and genetics of new autosomal STR loci useful for forensic DNA analysis.For. Sci. Rev. 2012; 24: 15
- Tools for analysis of population statistics.Profiles DNA. 1999; 3: 14-16
- Arlequin suite ver 3.5: a new series of programs to perform population genetics analyses under Linux and Windows.Mol. Ecol. Resour. 2010; 10: 564-567
Published online: September 09, 2015
Accepted: September 7, 2015
Received: August 18, 2015
© 2015 Published by Elsevier Inc.