Polymorphism Studies Of The 3 MiniSTR Loci D10S1248,D14S1434 And D22S1045 Of Han Ethnic In The Northeast Of China

Objective: As for human palaeontology and forensic degraded materials, short tandem repesats(STR) may fail to make the right conclusion. MiniSTR is a kind of new technology for STR typing. In order to make it closer to the core repeats region, the primer sequences are redesigned and these new markers produce short PCR products at the range of 50 ~ 150 base pairs (bp). Due to the small size of miniSTR products, it can be more effective to get the right typing from degraded materials. MiniSTR has been demonstrated to be an effective approach to recover genetic information from degraded or microamount samples. In this study, polymorphism of three miniSTR loci D10S1248, D14S1434, and D22S1045 were investigated in Han ethnic in northeast of China population, to obtain the population genetics data and forensic parameters of the allele frequencies, genotype frequencies, power of discrimination, polymorphism information content, etc., and to discuss the value of the 3 miniSTR in Anthropolgy and Forensic medicine in the population from northeast of China.Methods: 141 healthy unrelated Han ethnic individuals from northeast of China (including Liaoning, Jilin, and Heilongjiang Province) were selected, who lived in northeast of China at least 3 generations. Genome DNA was extracted with chelex-100 from 2ml EDTA-blood sample. The upstream and downstream primers were synthesized according to the DNA sequence, with 5'end fluorescence dye labled in the upstream primers. D10S1248 locus was labled with 6-FAM, blue fluorescence; D14S1434 locus was labled with HEX, green fluorescence and D22S1045 locus was labled with TAMRA, yellow fluorescence. Multiple fluorescent polymerase chain reaction(PCR)within the three loci were contained in one tube, then ABI 310 Genetic Analyzer was utilized in capillary electrophoresis and length of allele fragments was analyzed. Genetic data collection and analysis software were used for data collection and genotyping. Allele frequencies and genotype frequencies were calculated by direct counting. PowerStatsV1.2 software was used to analyze heterozygosity, power of discrimination, polymorphism information content, power of exclusion and typical paternity index. The GENEPOP software package was used to analyze the Hardy–Weinberg equilibrium test. The Arlequin3.11 software package was use to compare population differentiation with previous studies of other countries and districts.Results:1.The alleles and allele frequencies: Totally 25 alleles were checked out in the 3 miniSTR of Han nationality Chinese from northeast of China, the allele frequencies were at the range from 0.0035 to 0.4007; 56 genotypes were examined in total, the frequencies were at the range from 0.0071 to 0.2340. 8 alleles and 19 genotypes were checked in the D10S1248 locus, and the frequencies were at the range of 0.0035~0.3652 and 0.0071~0.1845, respectively; 8 alleles and 18 genotypes in the D14S1434 locus with the frequencies at the range of 0.007~0.401 and 0.0071~0.2340, respectively; 9 alleles and 19 genotypes in the D22S1045 locus with the frequencies at the range of 0.0035~0.2695 and 0.0071~0.1418, respectively. The genotype frequency distributions in the three miniSTR loci showed no deviations from Hardy–Weinberg equilibrium. 2. The heterozygosity, power of discrimination, polymorphism information content, power of exclusion, and typical paternity index: the observed heterozygosities of the three loci were 0.8085, 0.7234, 0.7943, respectively; the power of discrimination were 0.891, 0.877, 0.907, respectively; the polymorphism information contents were 0.72, 0.67, 0.73, respectively; the power of exclusion were 0.589, 0.465, 0.537, respectively; the typical paternity index were 2.43, 1.81, 2.14, respectively. The accumulated powers of discrimination and the accumu- lated power of exclusion for the three loci were 0.99876 and 0.89819, respectively. 3. Comparison with other population: Comparison studies on allele frequencies of the 3 miniSTR were performed with other populations. Compared with Chinese Han studied by R.B. etc. all the loci showed no significant difference (P>0.05) with the exception of D14S1434 locus (P=0.014); compared with Korean ethnic Chinese, significant difference could be established in all of the loci (P<0.05) excluding D10S1248 locus (P=0.992); compared with Singapore Chinese, all the loci showed no significant difference (P>0.05) with the exception of D22S1045 locus (P=0.043); compared with Singapore Malay and Indian, significant difference could be established in all of the loci (P<0.05); compared with Japanese, all the loci showed significant difference (P<0.05) with the exception of D10S1248 locus (P=0.629); compared with Korean, all the loci showed significant difference (P<0.05) with the exception of D10S1248 locus (P=0.966); compared with Spanish, African American, Caucasian, and Hispanic, all the loci showed significant difference (P<0.05).Conclusion: 1. The miniSTR polymorphisms could be observed at all of the three loci in Han ethnic Chinese of northeast of China. The data obtained from this study would do benefit to understand the population genetics of the three miniSTR loci in this population. 2. The allele distribution characters of the three miniSTR loci were analyzed in Han ethnic Chinese of northeast of China and the high percentage of the accumulated power of discrimination and the accumulated power of exclusion existed in the three miniSTR loci would be greatly beneficial for the population genetics, human palaeontology and forensic analysis.