[Multiplex PCR and genetic polymorphism of STR loci D4S1627, D14S1426, D1S1649].

OBJECTIVE: To prepare the allelic ladder materials of three STR loci includes D1S1649, D4S1627, D14S1426, and construct a synchronous detection method by multiplex amplification of the three loci. METHODS: Multiplex PCR method, PAGE (polyacrylamide gel electrophoresis) and silver staining were applied to detect 120 unrelated Chinese Han population from Chengdu whose allele and gene frequency distributing of these three loci. The electrophoretic bands of the multiplex PCR of these three loci were clear, no overlap of each alleles were observed, and the results were the same with single-locus test results. The results of the multiplex PCR demonstrated that the genotype of these three STR loci in Chengdu Han population in the genotype distribution met with Hardy-Weinberg equilibrium. 6 alleles (10-15) were detected in D4S1627, 9 alleles(5, 6, 8-14, without 7) were detected in D14S1426, 6 alleles (7-12) were detected in D1S1649. CONCLUSION: The results suggested that the multiplex PCR system of these three loci is of practical value in genetic research and forensic identification.

Genetic polymorphisms of DNA repair gene XRCC1 and risk of uterine leiomyoma.

The objective was to study the relationship between the polymorphisms of the DNA repair gene XRCC1 Arg399Gln, Arg194Trp, and Arg280His uterine leiomyoma in a Chinese population. In the case-control study, we compared the XRCC1 gene polymorphism of 136 uterine leiomyoma patients and 140 healthy controls by using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The results suggested that the genotype Arg/Arg of codon 280 was significantly different from its heterozygote (odds ratio [OR] = 3.633, 95% confidence interval [CI]: 2.147-6.148). In conclusion, the results suggest that polymorphism of XRCC1 Arg280His was associated with the increased risk of uterine leiomyoma in a Chinese population.

[The expression of BDNF and PSD-95 in hippocampal CA1 region of morphine-withdrawn rat with different dependent times].

OBJECTIVE: To observe the expression of brain-derived neurotrophic factor (BDNF) and postsynaptic density-95 (PSD-95) in hippocampal CA1 region of rat with morphine dependence for different times and withdrawn for 1 week, and investigate the influence of that morphine dependence is withdrawn on rat hippocampal CA1 area. METHODS: Animal models of rats with morphine withdrawal for 1 week and different morphine dependent times(1 week, 2 weeks, 4 weeks) were established. The expression of BDNF and PSD-95 in hippocampal CA1 were identified with RT-PCR. RESULTS: The expression of BDNF and PSD-95 in hippocampal CA1 decreased in the withdrawn group with morphine dependence for 1 week as compared with that in normal saline (NS) group (P < 0.01), and it increased in the withdrawn group with morphine dependence for 2 weeks as compared with that in morphine-dependent group for 1 week (P < 0.05) but still decreased as compared with that in NS group (P < 0.01), and it decreased in the withdrawn group with morphine dependence for 4 weeks as compared with the other three groups (P < 0.01). CONCLUSION: The expression of BDNF and PSD-95 in hippocampal CA1 decreases in morphine-depended rats withdrawn for 1 week. Morphine withdrawal has a manifest harm in hippocampal CA1 region of rat.

[Genetic polymorphisms of five STR gene loci GATA30F04, GATA23B10, D18S847, GATA83B04 and GATA167A05 alleles in Chinese Han population of Chengdu area].

OBJECTIVE: To get the preliminary genotype and allele frequency distributions of GATA30F04, GATA23B10, D18S847, GATA83B04 and GATA167A05 loci in Chinese Han population in Chengdu area, and to validate more short tandem repeat (STR) systems for forensic application. METHODS: The polymerase chain reaction (PCR) was used to this study. Five STRs (GATA30F04, GATA23B10, D18S847, GATA83B04 and GATA167A05) were amplified from DNA samples, which were extracted with Chelex-100 method from EDTA-blood of 100 unrelated individuals. The PCR products were analyzed by PAG vertical electrophoresis. RESULTS: No deviations from Hardy-Weinberg equilibrium were observed. The expected heterozygosities observed were 0.694, 0.918, 0.836, 0.889 and 0.880 for GATA30F04, GATA23B10, D18S847, GATA83B04 and GATA167A05 respectively. The discriminating powers were 0.697, 0.901, 0.875, 0.900 and 0.891. CONCLUSION: The last four loci in this study are useful markers for genetics purposes in individual identification and paternity test.

[Genetic polymorphisms at five STR loci in Chengdu Han population].

OBJECTIVE: To understand the allele structure and genetic polymorphisms at five STR loci in Chengdu Han population, to obtain a preliminary database and to analyze the value in forensic medicine. METHODS: EDTA-blood specimens were collected from unrelated individuals. The DNA of samples was extracted with Chelex-100 method. And then the PCR amplification, PAGE horizontal electrophoresis and gel silver staining were performed for analyzing the polymorphisms of five STR loci in Chengdu Han population. RESULTS: In the five STR loci,10, 7, 5, 7 and 7 alleles were found respectively. The observed heterozygosity of 83%, 80%, 64%, 66% and 77% and discrimination power of 95.44%, 91.0%, 84.3%, 86.1% and 86.8% were identified for the five STR loci respectively. All loci obeyed Hardy-Weinberg equilibrium. CONCLUSION: The five STR loci display the high discrimination power. The obtained data are desirable for forensic analysis and benefiting to the research of the population genetics.

[Polymorphism of five short tandem repeat systems in Chinese Han population in Chengdu].

OBJECTIVE: To obtain population genetic data of loci D11S4951, D11S4957, GATA193H05, D2S2951, and D6S2421 in Han population in Chengdu area and to validate the value of their forensic application. METHODS: Blood samples were collected in EDTA tubes from unrelated individuals. DNAs were extracted with Chelex-100 and were analyzed by PCR and horizontal PAGE followed by silver staining. RESULTS: Alleles 7, 10, 8, 6 and 8 were found in 5 STR loci, respectively. No deviations from Hardy-Weinberg balance were observed. The heterozygosities observed were 0.743, 0.772, 0.833, 0.650 and 0.800, respectively. The chances of exclusion were 0.497, 0.549, 0.662, 0.356 and 0.599, and the discrimination powers were 0.863, 0.912, 0.947, 0.829 and 0.931. CONCLUSION: All of the five loci studied may be useful markers for individual identification and paternity testing.

[Genetic polymorphisms of three loci and implication to forensic medicine].

OBJECTIVE: To obtain population genetic data of short tandem repeat (STR) locus D2S1327, D1S1390, and D11S2008 and to investigate the disparity of allelic frequency distributions among populations from different regions. METHODS: Blood samples of 300 unrelated individuals from Chengdu (Han), Bangkok (Thai) and Maint (Germany) were taken and analyzed with single PCR, polyacrylamide gel electrophoresis and silver staining. RESULTS: In the three loci, 9, 6, and 8 alleles and 32,14, and 22 genotypes were found respectively. The observed heterozygosity of 79%-82%, 63.0%-74.3%, and 72.0%-74.3% and discrimination power of 87.8%-92.6%, 79.6%-82.5%, and 87.6%-89.0% were identified for the three loci respectively. The genotype distributions of the three loci in the three populations fitted well with Hardy-Weinberg equilibrium. There was no significant difference in allelic frequency distributions among the three populations. CONCLUSION: The methods described in this paper are easy to perform and have high sensitivities. The discrimination power and exclusion chances of these three loci are desirable for forensic analysis and application.

[Analysis of the multi-amplified 5 STR loci and their allelic distribution in both Han populations in Chengdu City and Yunnan province].

OBJECTIVE: To illuminate the multi-amplified 5 STR loci and their allelic distribution in Hans by means of STR-DNA typing with improved efficiency and decreased cost. METHODS: We have established an allelic ladder of D7S820, D13S317, D5S818, D3S1358 and Amelogenin loci via the cloning techniques. With this homemade allelic ladder, we established successfully a multiplexing polymerase chain reaction (PCR) method, followed by denaturing polyacrylamide gel electrophoresis (PAGE) and silver staining. DNA samples collected from 130 unrelated Han individuals in Yunnan and Chengdu were analyzed. The non-overlapping of the allelic fragments of the five loci allowed the detection to be accomplished successfully. RESULTS: No difference of the genotyping results of the single locus amplification and multiplexing was observed. The genotype distributions of 4 STR were in accordance with the Hardy-Weinberg equilibrium. 7, 7, 8 and 8 alleles of D7S820, D13S317, D5S818, and D3S1358 loci were observed in Yunnan Han population, as well as 8, 7, 8 and 7 alleles in Chengdu Han population respectively. No significant difference in the allele distribution of these loci was seen between these two Han populations. CONCLUSION: This multiplexing system with home-made allelic ladder has a high combined discrimination power and exclusion power. It is a valuable tool in forensic science practice.

[Primary study on the influence of blood transfusion on the STR genotypes of recipient's blood].

OBJECTIVE: To investigate whether any change occurred in recipients' blood collected at different times after transfusion with different quantity of blood. METHODS: Three patients were transfused with 400 ml, 800 ml and 1200 ml blood separately. The blood samples were collected from the recipients before transfusion and at 4 h, 8 h, 12 h after transfusion, and from the donors. DNA were extracted by Chelex-100 method and were amplified by the polymerase chain reaction (PCR). Six loci of D1S549, D18S865, D3S1754, D12S391, D12S375, D6S477 were selected. The PCR products were analyzed by polyacrylamide gel (PAG) vertical electrophoresis and silver staining. RESULTS: The investigations on the six STR loci revealed that the patients' STR genotypes remained unchanged within 12 h after blood transfusion. CONCLUSION: The STR genotypes of the donors would have no influence on the STR genotypes of the patients within 12 h after transfusion providing the volume of blood transfused is less than 1200 ml.

[Analysis of p53 gene mutation in esophageal exfoliative cells].

OBJECTIVE: To explore the feasibility of detecting p53 gene mutation in exfoliative esophageal cells, and compare gene mutation between precancerous lesions and normal esophageal exfoliative cells and correlate p53 gene mutation with esophageal carcinogenesis. METHODS: Forty-eight samples (24 normal squamous epithelia and 24 severe squamous dysplasia) were obtained by balloon cytologic technique from a high incidence area, Yanting county, Sichuan Province, China in 1982. p53 gene mutations in exons 5 and 7 were analyzed by PCR-SSCP. RESULTS: p53 genes were detected in all samples. Five samples with p53 mutation were detected in exon 7 and no mutation was detected in exon 5 in 24 severe dysplasia samples. Three of the 5 samples with mutation in exon 7 developed esophageal cancer in 1992, 1994 and 1996 respectively. No p53 gene mutation was detected in exon 5 and 7 in normal exfoliative samples. CONCLUSION: p53 mutation may have occurred in the precancerous lesions which contributes in the initiation of human esophageal carcinogenesis.

[Polymorphisms of five short tandem repeat systems in Chinese Zang population in Kangba area].

OBJECTIVE: To get preliminary genotype and allele frequency distributions of D1S549, D3S1754, D12S391, D12S375 and D18S865 loci in Chinese Zang (Tibetan) population in Kangba area and to validate more short tandam repeat (STR) systems for forensic application. METHODS: Fresh samples of venous blood from 100 unrelated individuals of Chinese Zang population in Kangba area were dropped on the filter paper. After they dried up, DNA were extracted by chelex-100 method and amplified by the polymerase chain reaction (PCR). The PCR products were analyzed by PAG vertical electrophoresis and silver staining. RESULTS: Seven alleles were found at D1S549 locus, six alleles at D3S1754 locus, ten alleles at D12S391 locus, six alleles at D12S375 and six alleles at D18S865 locus. No deviations from Hardy-Weinberg equilibrium were observed. The heterozygosities observed were 0.86, 0.77, 0.81, 0.69, 0.80 for D1S549, D3S1754, D12S391, D12S375 and D18S865 respectively. The calculated values of the Power of Exclusion were 0.715, 0.545, 0.618, 0.413 and 0.599, and the values of the Power of Discrimination were 0.929, 0.838, 0.934, 0.886 and 0.890, respectively. CONCLUSION: All of the five loci in this study were useful for individual identification and paternity test, as well as for research purposes in genetics.

[Further study on heterogeneic basis of complement C8 beta deficiency].

OBJECTIVE: In Caucasian population, the most common molecular basis for C8 beta deficiency s a single C to T transition in exon 9 of C8 beta gene resulting in a stop codon. In previous family studies, two individuals were identified with C8 beta complete deficiency and were found to be only heterozygous for this mutation. This study was conducted by the present authors in search of other possible causes for these two C8 beta deficient individuals. METHODS: Using direct DNA sequence analysis of all exon-specific PCR products of the C8 beta gene from these two C8 beta deficient patients and their descendants. RESULTS: Two other C to T transitions at base 298 and 388 in exon 3 were detected, which could also create a termination codon. The descendants from one of the deficient patients were also analysed for the mutations, and it could be demonstrated that the two C to T mutations in exons 9 and 3 are segregating independently. CONCLUSION: These two mutations, which create a termination codon, are sufficient to explain the complete C8 beta deficiency in both patients.

[A study of forensic individual identification used STR locus with silver staining and multiplex PCR methods].

Amplification of short tandem repeat(STR) loci has become a useful tool for human identification applications. To improve throughput and efficiency for the forensic materials and gain foure and six STR locis multiplex methods with silver staining, CSF1PO,TPOX,THO1 and vWA(referred to as multiplex A), D18S51, D7S820, D13S317, D5S818, D3S1358 and Amelogenin(referred to as multiplex B) have been evaluated for use in a rape case. The products of multiplex amplication were separated in a denaturing polyacrylamide gel and analyzed with silver staining. Two multiplex amplications used in this case could provide a power of discrimination of approximately 2.43 x 10(-19). Silver staining was shown to be a validation methods for analysing the products of four and six multiplex amplications.