From Vietnamese plants to a biflavonoid that relieves inflammation by triggering the lipid mediator class switch to resolution

Chronic inflammation results from excessive pro-inflammatory signaling and the failure to resolve the inflammatory reaction. Lipid mediators orchestrate both the initiation and resolution of inflammation. Switching from pro-inflammatory to pro-resolving lipid mediator biosynthesis is considered as efficient strategy to relieve chronic inflammation, though drug candidates exhibiting such features are unknown. Starting from a library of Vietnamese medical plant extracts, we identified isomers of the biflavanoid 8-methylsocotrin-4'-ol from

Inhibition of bakuchiol and its derivatives in Psoraleae Fructus on nitric oxide production in lipopolysaccharide-activated RAW 264.7 cell lines / 中草药

Objective: To study bakuchiol and its derivatives of cyclohexane soluble part in 70% ethanol aqueous extract of Psoraleae Fructus and their inhibition on nitric oxide (NO) production in lipopolysaccharides (LPS)-activated murine macrophage RAW 264.7 cell lines. Methods: The compounds were separated and purified by silica gel column and high performance liquid chromatographies, and their structures were determined by spectroscopic data analyses. Using LPS-activated RAW 264.7 cell line models in vitro, all of the isolated compounds were evaluated for the inhibition against NO production. Results: Twelve compounds were obtained and identified as bakuchiol (1), 12,13-dihydro-12,13-epoxybakuchiol (2), Δ3,2-hydroxylbakuchiol (3), 12-oxobakuchiol (4), psoracorylifol B (5), psoracorylifol C (6), (12’S)-bisbakuchiol C (7), Δ1,3-bakuchiol (8), 13-methoxyisobakuchiol (9), bisbakuchiol B (10), bisbakuchiol A (11), and 12,13-dihydro-12,13-dihydroxybakuchiol (12), respectively. For the inhibition of NO production in the LPS-activated RAW 264.7 cell line model, a positive inhibitor, L-N6-(1-iminoethyl)-lysine (L-NIL), was used and showed the half maximal inhibitory concentration (IC50) value of (10.29 ± 1.10) μmol/L. The IC50 values of the assayed compounds 1, 3, 5, 10 and 11 were all more than 50 μmol/L, compounds 8, 9 and 12 were comparable to that of L-NIL, whereas the IC50 values of compounds 2, 4 and 7 were less than that of the positive inhibitor with statistically significance. Conclusion: Compound 4 is a new natural product. The results of the bioactivity assays indicated that compounds 2, 4, 7, 8, 9 and 12 are potential anti-inflammatory agents.

Comparison of phenol-chloroform and a commercial deoxyribonucleic acid extraction kit for identification of bloodmeal sources from triatomines (Hemiptera: Reduviidae)

Abstract INTRODUCTION: Knowledge of triatomine bloodmeal sources is essential for understanding vector-host interactions in Trypanosoma cruzi transmission cycles. Expensive commercial deoxyribonucleic acid (DNA) extraction kits are widely used for bloodmeal identification. This study assessed the performance of an inexpensive phenol-chloroform DNA extraction protocol for identification of triatomine bloodmeal sources, comparing it with a commercially available kit. METHODS: Both methods were used to obtain DNA from the intestinal contents of Triatoma brasiliensis blood-fed on either Columba sp., Mus musculus, or Gallus gallus. Subsequently, the mitochondrial 12S ribosomal ribonucleic acid (rRNA) gene was amplified by polymerase chain reaction, sequenced, and compared with GenBank data. RESULTS: Twelve (80%) samples extracted with the commercial kit and four (26.7%) with phenol-chloroform were pure (according to the A260/A280 ratio). Samples extracted with phenol-chloroform, except for Columba sp. samples, had higher DNA concentration than those extracted with the commercial kit. Samples extracted using phenol-chloroform and blood-fed on G. gallus had significantly higher DNA concentration than those blood-fed on Columba sp. (p-value <0.001) and M. musculus (p-value <0.001). The 215-base-pair 12S rRNA fragment was amplified from all samples and produced reliable sequences, enabling the identification of the bloodmeal source, most of which showed identity and coverage above 95%. The phenol-chloroform method was much less expensive than the commercial kit but took considerably more time to perform. CONCLUSIONS: Our data showed that both DNA extraction methods produced reliable sequences enabling identification of triatomine bloodmeal sources but differed greatly in cost and time required.

Detection of fraud by addition cow's milk in cheese buffalo and its connection with seasonality / Detecção de fraude por adição de leite de vaca em queijo de búfala e a relação com a sazonalidade

The seasons influence the production of buffalos' milk. Because of this, the producers may produce a mixture of buffalo and bovine milk during cheese production in periods of low production. Therefore, the present work aimed to investigate fraud in buffalo cheese and the relationship between seasonality and different physicochemical properties of buffalo cheeses produced and marketed in eastern Amazonia. We obtained commercial samples of buffalo cheese during two Amazonian climatic periods from commercial points of Marajó-Pará, Brazil. After collection, there were lipid, protein, ash, and humidity analyses. Determination of carbohydrates and energy values was also performed for the nutritional characterization of samples, as well as for mPCR analysis to detect buffalo and/or bovine DNA. DNA extraction protocol of the samples was standardized and two pairs were used for the mPCR reaction, amplifying fragments of approximately 220 bp for Bubalus bubalis DNA and 346 bp fragments for Bos taurus DNA. Among the samples acquired in the rainy season, we observed that 33% were inadequately labeled, indicating fraud from cow's milk incorporation and fraud from substitution of raw material. From the nine samples obtained in the dry season, all the samples showed cow's milk incorporation fraud. The highest fraud rate coincided with the period of low milk production from buffalo and there was a difference in composition between fraudulent and non-fraudulent cheeses. Therefore, seasonality influences increase in cattle milk for the production of buffalo cheese, and this adulteration may decrease the nutritional content of the product.

As estações climáticas influenciam a produção de leite de búfala. Isso pode levar os produtores a misturarem os leites de búfala e bovino durante a produção de queijo em períodos de baixa produção. Portanto, o presente trabalho teve como objetivo verificar fraudes em queijo de búfala, a relação com a sazonalidade e as diferenças físico-químicas de queijos de origem bubalina, produzidos e comercializados no leste da Amazônia. Foram coletadas amostras comerciais de queijo de búfala em dois períodos climáticos da Amazônia em pontos comerciais do Marajó-Pará, Brasil. Após a coleta foram realizadas análises de lipídios, proteínas, cinzas e umidade. A determinação dos carboidratos e do valor energético também foi feita para a caracterização nutricional das amostras, bem como a análise de mPCR para a detecção de DNA de búfalo e/ou bovino. Para isso, padronizou-se um protocolo de extração de DNA das amostras e utilizou-se dois pares na reação mPCR, amplificar fragmentos de aproximadamente 220 pb para o DNA de Bubalus bubalis e fragmentos de 346 pb para o Bos taurus. Entre as amostras adquiridas na estação chuvosa, observou-se que 33% foram rotuladas inadequadamente, caracterizando fraude por incorporação de leite de vaca e fraude por substituição de matéria-prima. Das 9 amostras coletadas no período seco, todas as amostras apresentaram fraude na incorporação do leite de vaca. Este estudo revelou que a maior taxa de fraude coincide com o período de baixa produção de leite e que há uma diferença na composição entre queijos fraudulentos e não fraudulentos. Portanto, a sazonalidade influencia no acréscimo de leite de bovinos na produção de queijo de búfala e que esta adulteração pode diminuir o conteúdo nutricional do produto.

Detection of fraud by addition cow's milk in cheese buffalo and its connection with seasonality / Detecção de fraude por adição de leite de vaca em queijo de búfala e a relação com a sazonalidade

The seasons influence the production of buffalos’ milk. Because of this, the producers may produce a mixture of buffalo and bovine milk during cheese production in periods of low production. Therefore, the present work aimed to investigate fraud in buffalo cheese and the relationship between seasonality and different physicochemical properties of buffalo cheeses produced and marketed in eastern Amazonia. We obtained commercial samples of buffalo cheese during two Amazonian climatic periods from commercial points of Marajó-Pará, Brazil. After collection, there were lipid, protein, ash, and humidity analyses. Determination of carbohydrates and energy values was also performed for the nutritional characterization of samples, as well as for mPCR analysis to detect buffalo and/or bovine DNA. DNA extraction protocol of the samples was standardized and two pairs were used for the mPCR reaction, amplifying fragments of approximately 220 bp for Bubalus bubalis DNA and 346 bp fragments for Bos taurus DNA. Among the samples acquired in the rainy season, we observed that 33% were inadequately labeled, indicating fraud from cow’s milk incorporation and fraud from substitution of raw material. From the nine samples obtained in the dry season, all the samples showed cow’s milk incorporation fraud. The highest fraud rate coincided with the period of low milk production from buffalo and there was a difference in composition between fraudulent and non-fraudulent cheeses. Therefore, seasonality influences increase in cattle milk for the production of buffalo cheese, and this adulteration may decrease the nutritional content of the product.

As estações climáticas influenciam a produção de leite de búfala. Isso pode levar os produtores a misturarem os leites de búfala e bovino durante a produção de queijo em períodos de baixa produção. Portanto, o presente trabalho teve como objetivo verificar fraudes em queijo de búfala, a relação com a sazonalidade e as diferenças físico-químicas de queijos de origem bubalina, produzidos e comercializados no leste da Amazônia. Foram coletadas amostras comerciais de queijo de búfala em dois períodos climáticos da Amazônia em pontos comerciais do Marajó-Pará, Brasil. Após a coleta foram realizadas análises de lipídios, proteínas, cinzas e umidade. A determinação dos carboidratos e do valor energético também foi feita para a caracterização nutricional das amostras, bem como a análise de mPCR para a detecção de DNA de búfalo e/ou bovino. Para isso, padronizou-se um protocolo de extração de DNA das amostras e utilizou-se dois pares na reação mPCR, amplificar fragmentos de aproximadamente 220 pb para o DNA de Bubalus bubalis e fragmentos de 346 pb para o Bos taurus. Entre as amostras adquiridas na estação chuvosa, observou-se que 33% foram rotuladas inadequadamente, caracterizando fraude por incorporação de leite de vaca e fraude por substituição de matéria-prima. Das 9 amostras coletadas no período seco, todas as amostras apresentaram fraude na incorporação do leite de vaca. Este estudo revelou que a maior taxa de fraude coincide com o período de baixa produção de leite e que há uma diferença na composição entre queijos fraudulentos e não fraudulentos. Portanto, a sazonalidade influencia no acréscimo de leite de bovinos na produção de queijo de búfala e que esta adulteração pode diminuir o conteúdo nutricional do produto.

СОНСГОЛЫН ХҮНД ХЭЛБЭРИЙН БУУРАЛТТАЙ ХҮНД CONNEXIN 26 ГЕНИЙН МУТАЦИЙГ ТОДОРХОЙЛСОН ТӨСӨЛТ АЖЛЫН ЗАРИМ ҮР ДҮН / Шинэ санаа Шинэ нээлт

@#BACKGROUND. Sensorineural hearing impairment (SNHI) is the most common inherited sensory defect, affecting about 3 per 1000 children. More than 50% of these patients have a genetic cause (i.e. hereditary hearing impairment; HHI). Mutations in certain genes were noted to be extraordinarily popular in the deaf patients across different populations, making molecular screening feasible for these common deafness genes. One of the most important characteristics that we have learned concerning hereditary hearing loss is that common deafness genes and their mutations are usually different according to the ethnic background. As demonstrated in our previous studies performed in Taiwanese patients, the mutation spectrums of common deafness genes, such as the GJB2 gene and the SLC26A4 gene, are different from those in the Caucasian or even other Asian populations. These findings further underscore the indispensability of the collection of local data in terms of genetic counseling. In the collaborative project, we have successfully established a cohort of >100 hearingimpaired families, and clarified the genetic epidemiology of deafness in the Mongolian population. We identified several special deafness mutations such as GJB2 c.23+1G>A, c.559_604dup, and SLC26A4 c.919-2A>G, and our results revealed that Mongolian patients demonstrate a unique genetic profile in deafness as compared to other East Asian populations (paper in preparation). Meanwhile, by organizing a seminar at National Taiwan University Hospital in March 2017, we have transferred crucial concepts and techniques regarding how to perform genetic testing for deafness to the Mongolian colleagues. In the future, we plan to strengthen the mutual collaboration by expanding the clinical cohort and upgrading the genetic examination platform using the NGS techniques.

Rapid identification of Gekko gecko by loop-mediated isothermal amplification based on 12S rRNA sequence / 中国中药杂志

Gekko gecko (Tokay Gecko) is a valuable traditional Chinese medicine. In this study, the loop-mediated isothermal amplification (LAMP) technique was introduced for visual rapid identification of G. gecko from adulterants. A total of sixty-five 12S rRNA sequences of fourteen species of G. gecko and its adulterants were obtained. The results showed that G. gecko could be identified from its adulterants through BLAST analysis based on 12S rRNA regions. The 12S rRNA sequences of ten batches of G. gecko were conserved. There were only two haplotypes and three variation sites in the available regions for primers design. Six specific LAMP primers were successfully designed online based on 12S rRNA sequences. The visual rapid detection of G. gecko could be achieved with the optimized conditions (64 °C for 1 h and 80 °C for 5 min). And the required minimal template concentration was 5 μg·L⁻¹ while conventional PCR with 0.5 mg·L⁻¹. Consequently, the LAMP method established from this study was rapid, specific, highly sensitive, and simple. It could be applied to detect G. gecko from its adulterants efficiently.

Application progress on mitochondrial DNA markers in identification of animal medicinal materials / 中草药

Animal medicinal materials are important parts of traditional Chinese medicine (TCM) with a long history and remarkable efficacy. Due to the destruction of wild animal resources and increasingly market demands, the adulterations of animals medicinal materials have become more common in medicine market and bring security risks for clinical application. In recent years, mitochondrial DNA is widely used in the field of animal population genetics, phylogeography, and phylogenetic development due to its maternally inherited features and abundant genetic diversity, and has achieved fruitful results in the field of molecular identification, which provides technical support for quality control of animal medicinal materials. This paper summarizes the application value and research status of COI, Cyt b, and 12S rRNA in the identification of animal medicinal materials, and gives a brief discussion on the follow-up development of mtDNA marker technique in the identification of animal medicinal materials in combination with previous result, which provides technical support for reasonable utilization of medicinal animal resources.

Analysis of deafness-associated mutant genes and pedigrees in neonates / 预防医学

Objective To carry out mutation analysis of deafness-associated genes for deaf newborns and their parents, and to estimate the recurrence risk for their parents to have deaf descendants.Methods Suspected cases of inherited deafness were identified by neonatal hearing screening and questionnaires. Genomic DNAs of suspected cases and their parents were extracted from their peripheral blood samples . Common deafness-associated genes(i.e. GJB2,SLC26A4 and 12S rRNA genes)were amplified by polymerase chain reaction(PCR),and those PCR products were sequenced for the mutation analysis.Results From 2013 to 2016, 193 cases of deafness were found in neonatal hearing screening,29 cases of suspected as hereditary deafness were screened,and 17 out of 29 cases were found to have mutations in deafness-associated genes(detection rate:58.62%). GJB2 homozygous mutations were identified in two cases and their parents,and the recurrence risk to have deaf descendants was 100%. Four cases of suspected hereditary deafness had GJB2 homozygous mutations,and their parents were both GJB2 mutation carriers. There was one case with SLC26A4 homozygous mutations,and their parents were both SLC26A4 mutation carrier. Two cases were detected to have GJB2 V371 homozygous mutations,and their parents were both GJB2 V371 mutation carriers. For those seven parents carrying deafness-associated mutations above,the recurrence risk of deafness for their descendants was 25%.Conclusion In addition to hearing screening,the genetic diagnosis of deafness-associated genes is helpful to clarify the cause of suspected neonatal hereditary deafness,and can provide objective reproductive counseling and guidance for those deaf parents or parents with deaf children.

МОНГОЛ ХҮНИЙ ТӨРӨЛХИЙН БОЛОН ОЛДМОЛ ХЭЛБЭРИЙН ДҮЛИЙН ҮЕИЙН CONNEXIN 26 ГЕНИЙН МУТАЦИЙГ ТОДОРХОЙЛСОН СУДАЛГААНЫ АЖЛЫН ЗАРИМ ҮР ДҮН / Шинэ санаа Шинэ нээлт

@#BACKGROUND. Sensorineural hearing impairment (SNHI) is the most common inherited sensory defect, affecting about 3 per 1000 children. More than 50% of these patients have a genetic cause (i.e. hereditary hearing impairment; HHI). Mutations in certain genes were noted to be extraordinarily popular in the deaf patients across different populations, making molecular screening feasible for these common deafness genes. One of the most important characteristics that we have learned concerning hereditary hearing loss is that common deafness genes and their mutations are usually different according to the ethnic background. As demonstrated in our previous studies performed in Taiwanese patients, the mutation spectrums of common deafness genes, such as the GJB2 gene and the SLC26A4 gene, are different from those in the Caucasian or even other Asian populations. These findings further underscore the indispensability of the collection of local data in terms of genetic counseling. In the collaborative project, we have successfully established a cohort of >100 hearing-impaired families, and clarified the genetic epidemiology of deafness in the Mongolian population. We identified several special deafness mutations such as GJB2 c.23+1G>A, c.559_604dup, and SLC26A4 c.919-2A>G, and our results revealed that Mongolian patients demonstrate a unique genetic profile in deafness as compared to other East Asian populations (paper in preparation). Meanwhile, by organizing a seminar at National Taiwan University Hospital in March 2017, we have transferred crucial concepts and techniques regarding how to perform genetic testing for deafness to the Mongolian colleagues. In the future, we plan to strengthen the mutual collaboration by expanding the clinical cohort and upgrading the genetic examination platform using the NGS techniques.

The identiifcation analysis of rhinoceros horns products based on DNA barcoding 12s rRNA / 中国法医学杂志

Objective Through the DNA barcoding 12s rRNA sequences alignment and analysis of several rhinoceros horns products involved in cases to analysis the application feasibility of 12s rRNA in the rhinoceros horns products’ species identification. Methods Use rhinoceros horns products in 3 cases as materials, total DNA were extracted with improved method, PCR ampliifcation the DNA barcoding. Results The alignment and analysis of sequences show that 12s rRNA could identify rhinoceros horns products at the species level. Conclusion The DNA barcoding 12s rRNA could be used as a new way to identify the rhinoceros horns products which can’t be identiifed with morphological characteristics, provide a reliable basis for the qualitative and sentencing of cases.

Expression of miR-181a and CA125 and their correlation in human type I and II endometrial carcinoma / 解放军医学杂志

Objective To investigate the expression and correlation of microRNA-181a (miR-181a) and CA12S in human types I and II endometrial carcinomas. Methods A total of 78 formalin-fixed and paraffin-embedded endometrium tissue specimens were used in the present study, and they were supplied by Xiaolan People's Hospital affiliated to Southern Medical University, Southern Hospital and Zhongshan Hospital affiliated to Zhongshan University during Jan. 2011 to Dec. 2013. Among them, 13 were determined as normal endothelium by pathological and examination with immunohistochemical staining, 18 were endometrial hyperplasia, and 47 of them diagnosed were as endometrial carcinoma (type I 37 and type E 10). Total RNA was extracted from each of the specimens, and then the expression of miR-181a was determined by real-time PCR, and the expression of CA125 was detected by immunohistochemical staining. Results The expression levels of both miR-181a and CA125 were obviously higher in type I and II endometrial carcinoma tissues than in normal tissue (P<0.05). In addition, the expression of miR-181a was significantly higher in type II endometrial carcinoma than in type I endometrial carcinoma and endometrial hyperplasia tissues (P<0.05). Moreover, it was found that the expression of miR-181a increased gradually from that of normal endometrium to endometrial hyperplasia and then endometrial carcinoma, with statistically significant difference among them (P<0.05). In addition, there was also a significant difference in the expression of CA12S in different types of endometrial carcinoma (P<0.05). Correlation analysis showed that the expressions of miR-181a and CA12S were negatively correlated with each other in the process of carcinogenesis of endometrium (P<0.05). Conclusion There is a difference in expression of miR-181a between type I and type II endometrial carcinoma, and it may be related to the development and progression of endometrial carcinoma. The mechanism may be related to the expression of CA12S as regulated by miR-181a in the process of endometrial carcinogenesis, but the specific mechanism still needs further validation with experiments on the cellular level.

Value of ADAM12-S in early diagnosis of ectopic pregnancy of pregnant women / 中国生化药物杂志

Objective To determine the values and variation tendency of a disintegrin and metalloprotease 12-S(ADAM12-S)of early pregnancy, and discuss the value of ADAM12-S to the ectopic pregnancy in the first trimester.Methods 150 early pregnancy cases (from the 5th to 10th week of pregnancy)were selected in Huanggang Women &Children's Healthcare Hospital.There were 102 cases of normal pregnancy,48 cases of ectopic pregnancy.The AutoDELFIA immunoassay platform was used to measure the value of ADAM12-S in the serum.Results Of the 102 normal pregnancies, the values of ADAM12-S in 5th-10th week of pregnancy linearly increase with gestationalage.The correlation coefficient was 0.9217 (P<0.05).While the values of ADAM12-S in the ectopic pregnancy group were significantly lower than the normal pregnancy group and not linearly increased with gestationalage.The correlation coefficient was 0.2817.There was statistically significant difference between the two groups (P<0.05).Conclusion The values of ADAM12-S is stable in the first trimester of normal pregnancy,while it is much more lower in abnormal pregnancy.ADAM12-S has great significance in the diagnosis of ectopic pregnancy of the first trimester.

Effect of 12(S)-HETE on the p27~(kip1) expression in rat mesangial cells and glomeruli / 中国免疫学杂志

Objective:To investigate the effect of 12(S)-HETE on the p27~(kip1) expression in mesangial cells and glomeruli.Methods:Mesangial cells were exposed to 12(S)-HETE.12(S)-HETE was infused to rats by osmotic mini-pump.Total protein content measurement for cell hypertrophy,RT-PCR for mRNA expression and Western blot for protein expression were performed respectively.Results:12(S)-HETE stimulation induced mesangial cell hypertrophy and p27~(kip1) protein expression,but not p27~(kip1) mRNA expression.Furthermore,p27~(kip1) mRNA and protein expression in the glomeruli were significantly increased by 12(S)-HETE stimulation using osmotic mini-pump.Conclusion:12(S)-HETE plays an important role in the pathogenesis of glomerular cell hypertrophy and senescence through upregulation of p27~(kip1) expression.

Changes of expression levels of 12S rRNA and COXⅠ mRNA encoded by mtDNA in rat brain during hypoxic exposure / 第三军医大学学报

Objective To explore the changes of expression levels of 12S rRNA and cytochrome oxidase subunit Ⅰ (COXⅠ) mRNA encoded by mtDNA in rat cerebral cortex after rat exposure to hypobaric hypoxia for different days. Methods Healthy male Wistar rats were exposed to hypobaric chamber simulating 5 000 m above sea level (23 5 h/day) for 2, 5, 15 and 30 d. Rats in the control group were not exposed to hypoxia. Rats were sacrificed by decapitation. Total RNA in cerebral cortex was extracted using a standard program. Transcriptional levels of 12S rRNA and COXⅠ mRNA were determined by reverse transcription polymerase chain reaction (RT PCR). Results Compared with that in the control, the expression of 12S rRNA increased by 57% after hypoxic exposure for 2 d ( P 0 05). Compared with that in the control group, the expression of COXⅠ mRNA increased significantly by 55% and 106% after hypoxic exposure for 2 and 5 d ( P 0 05). Conclusion Hypoxic exposure may have effect on both protein gene and ribosome gene expression encoded by mtDNA, and the expression changes in a hypoxic exposure time dependent manner. This suggests that hypoxia can have effect on mitochondrial oxidative phosphorylation gene expression at both mitochondrial transcriptional and translational levels.

Population Genetics of the Hypervariable Locus D12S391 in Korean / 대한법의학회지

The hypervariable short tandem repeat (STR) locus D12S391 was investigated in a Korean population. A total of 14 alleles were detected by size under denaturing conditions in 517 unrelated individuals. To confirm all of the alleles detected in a Korean population, a total of 34 fragments were sequenced. Prior to allele designation, we constructed the allelic ladders containing 11 alleles sequenced in this study. Allele 18 is the most common with a frequency of 0.281 in Koreans, and one variant allele 19.3 which have been confirmed by sequencing, was detected. The observed heterozygosity, the power of discrimination (PD), and the mean exclusion chance (MEC) for the locus D12S391 is 0.781, 0.946 and 0.652, respectively. No deviation from Hardy-Weinberg equilibrium was observed in a Korean population (p=0.557). In the 424 meioses in 105 Korean families confirmed using other 17 STR loci, no mutation was detected in locus D12S391. The STR locus D12S391system is useful both for the analysis identification and parternity.

Study on the construction of standard D12S375 allelic ladder and its genetic polymorphism in Chinese Han, Hui and Wei populations / 中国法医学杂志

s:To resolve the problem of the accuracy and standardization of STR PCR typing in forensic science practice,we have designed a new method to produce standard D12S375 allelic ladder.Seven different PCR amplified D12S375 allelic fragments were isolated from the gel,eluted into the distilled water and reamplified by PCR.The purified allelic fragments were then blunt end subcloned individually into the pUC plasmid vectors and transfected into competent E.coli DH5? TM cells.The sequencing results confirmed that the size and the constructure of the inserts were correct.The recombinant plasmids DNA with 7 inserts were then used as templates for reamplification to generate D12S375 standard ladder, with which the genetic polymorphisms of D12S375 locus in Chinese Han population in Chengdu,Hui population in Gansu and Wei population in Xinjiang were studied.