Genetic polymorphism of 23 autosomal STR loci in Han population from Yuncheng, Shanxi Province / 中南大学学报(医学版)

OBJECTIVES@#Due to the genetic feature of high diversity than other DNA markers, short tandem repeat (STR) plays key roles in forensic, anthropology, and population genetics. Newly introduced multiple STR kit is more valuable because of the greatly improved discriminatory power with the increase in the number of STR loci. The genetic polymorphic data are essential for the application and research in specific population. This study aims to investigate the genetic polymorphism of Han population residing in Yuncheng district, Shanxi Province, to evaluate the application of 23 STR loci in forensic personal identification and paternity test, and to explore the genetic relationship of Han population between Yuncheng and other populations.@*METHODS@#A total of 23 STR loci were amplified from 525 healthy unrelated individuals from the Han nationality in Yuncheng, Shanxi Province using the AGCU EX25 amplification kit. The products were detected and separated by ABI 3500 Genetic Analyzer. Alleles were genotyped by GeneMapper ID (Version 3.2) software, and corresponding frequencies and forensic parameters were calculated. We calculated the genetic distance and plotted the neighboring-joining tree with other 13 population.@*RESULTS@#The allele frequency of the 23 STRs ranged from 0.0010 to 0.5090. No deviation from Hardy-Weinberg equilibrium (@*CONCLUSIONS@#These 23 STRs are highly genetic polymorphic and informative in the Han population of Yuncheng, Shanxi Province, which can provide basic data for forensic personal identification, paternity testing, and population genetic research.

ISSR Analysis of Genetic Relationship and Population Structure of Turpinia arguta Fresh Leaves in Jiangxi Province / 中国实验方剂学杂志

Objective:To explore genetic relationship and population structure of Turpinia arguta in six locations of Jiangxi province by inter-simple sequence repeat （ISSR） molecular marker technique， and to provide theoretical basis for the protection and utilization of this medicinal material resource. Method:A total of 22 samples from six locations in four counties in Jiangxi province were collected， and genomic DNA was extracted by kit method. Polymerase chain reaction （PCR） amplification was performed using sixty-four universal ISSR molecular marker primers， and the products were detected with polyacrylamide gel electrophoresis （PAGE）. NTsys 2.10e software was selected to calculate the genetic similarity coefficient by unweighted pair group method with arithmetic mean （UPGMA） and cluster analysis. Population genetic structure was analyzed by Structure 2.1 software. Result:A total of forty-eight ISSR primers were amplified to obtain the product， the percent of polymorphic bands ranged from 45.45% to 100%. UPGMA cluster analysis showed that these plant individuals could not be clustered according to their respective executive locations. Analysis of population genetic structure showed that 22 samples of T. arguta could be divided into three populations. Conclusion:There is gene exchange among the populations of T. arguta in Jiangxi province， and it can affect the genetic structure of germplasm resources from different geographical sources.

Study on genetic structure differences and adjustment strategies in different areas of China / 中华流行病学杂志

Objective To describe the genetic structure of populations in different areas of China,and explore the effects of different strategies to control the confounding factors of the genetic structure in cohort studies.Methods By using the genome-wide association study (GWAS) on data of 4 500 samples from 10 areas of the China Kadoorie Biobank (CKB),we performed principal components analysis to extract the fast and second principal components of the samples for the component two-dimensional diagram generation,and then compared them with the source of sample area to analyze the characteristics of genetic structure of the samples from different areas of China.Based on the CKB cohort data,a simulation data set with cluster sample characteristics such as genetic structure differences and extensive kinship was generated;and the effects of different analysis strategies including traditional analysis scheme and mixed linear model on the inflation factor (λ) were evaluated.Results There were significant genetic structure differences in different areas of China.Distribution of the principal components of the population genetic structure was basically consistent with the geographical distribution of the project area.The first principal component corresponds to the latitude of different areas,and the second principal component corresponds to the longitude of different areas.The generated simulation data showed high false positive rate (λ =1.16),even if the principal components of the genetic structure was adjusted or the area specific subgroup analysis was performed,λ could not be effectively controlled (λ ＞ 1.05);while,by using a mixed linear model adjusting for the kinship matrix,λ was effectively controlled regardless of whether the genetic structure principal component was further adjusted (λ =0.99).Conclusions There were large differences in genetic structure among populations in different areas of China.In molecular epidemiology studies,bias caused by population genetic structure needs to be carefully treated.For large cohort data with complex genetic structure and extensive kinship,it is necessary to use a mixed linear model for association analysis.

Study on genetic structure differences and adjustment strategies in different areas of China / 中华流行病学杂志

Objective To describe the genetic structure of populations in different areas of China,and explore the effects of different strategies to control the confounding factors of the genetic structure in cohort studies.Methods By using the genome-wide association study (GWAS) on data of 4 500 samples from 10 areas of the China Kadoorie Biobank (CKB),we performed principal components analysis to extract the fast and second principal components of the samples for the component two-dimensional diagram generation,and then compared them with the source of sample area to analyze the characteristics of genetic structure of the samples from different areas of China.Based on the CKB cohort data,a simulation data set with cluster sample characteristics such as genetic structure differences and extensive kinship was generated;and the effects of different analysis strategies including traditional analysis scheme and mixed linear model on the inflation factor (λ) were evaluated.Results There were significant genetic structure differences in different areas of China.Distribution of the principal components of the population genetic structure was basically consistent with the geographical distribution of the project area.The first principal component corresponds to the latitude of different areas,and the second principal component corresponds to the longitude of different areas.The generated simulation data showed high false positive rate (λ =1.16),even if the principal components of the genetic structure was adjusted or the area specific subgroup analysis was performed,λ could not be effectively controlled (λ ＞ 1.05);while,by using a mixed linear model adjusting for the kinship matrix,λ was effectively controlled regardless of whether the genetic structure principal component was further adjusted (λ =0.99).Conclusions There were large differences in genetic structure among populations in different areas of China.In molecular epidemiology studies,bias caused by population genetic structure needs to be carefully treated.For large cohort data with complex genetic structure and extensive kinship,it is necessary to use a mixed linear model for association analysis.

The study of Tibetan ancestry informative SNPs on high-altitude adaptive genes / 中国法医学杂志

Objective Selecting Tibetan ancestry informative SNPs base on high-altitude adaptation genes of Tibetan. Methods We developed a multiplex assay constituted of 87 SNPs located on EPAS1 and EGLN1 genes based on Agena Mas-sARRAY? genotyping system. 183 samples from Tibet plateau were genotyped. The genotypes of 2504 samples from 26 populations were downloaded from the 1000 genomes. Genetic frequency and population structure were analyzed and compared between Tibetan population and worldwide populations. Results SNPs that have distinctive distribution between Tibetan and other populations could be used as Tibetan AISNPs (Ancestry informative SNPs). We selected 23 SNPs has a separated principal genetic component in STRUCTURE result. Conclusion These 23 AISNPs we selected could be combined into ancestry informative SNP panels to improve the resolution of ancestry inference in East Asian, and provide clues for cases of biological material ancestry inference.

Evaluation of genetic diversity and population structure of genus Tripterygium based on SSR markers / 药学学报

The genus Tripterygium is an immune suppressor in the Chinese traditional medicines. Due to the habitat destruction and anthropogenic over-exploitation, the wild genus Tripterygium plants have decreased dramatically in recent years or even been endangered. It is critical to evaluate and protect genus Tripterygium wild resource. In this research, simple sequence repeat (SSR) molecular markers were applied to the investigation of the genetic diversity and genetic structure of 28 populations for genus Tripterygium (396 samples from 9 provinces in China). We found a high level of genetic diversity (percentage of polymorphic loci PPL=77.29%, Shannon's information index I=0.639 4; Nei's expected heterozygosity H=0.359 9) and high genetic differentiation among the populations (gene flow Nm=0.228 7). Based on Nei's genetic distance, the phylogenic tree of populations was constructed and 28 populations were divided into 6 clusters according to STRUCTURE clustering analysis. T. hypoglaucumwas was mainly divided into 3 clusters, including Sichuan, Yunnan and GuizhouChongqing. T. regelii was separated to cluster 4, while T. wilfordii was divided into two clusters:the transition type LQ and NY were divided into cluster 5, and the others were in cluster 6. These results provide a theory basis for the conservation of wild resource, research of genetic polymorphism and molecular marker for assisted breeding of genus Tripterygium.

Genetic structure of Antioquia Holstein from two SNPs and association with dairy traits / Estructura genética del Holstein Antioqueño a partir de dos SNP y asociación con características lecheras

Objective. Analyze the structure and genetic differentiation of a population of Antioquia Holstein cows from the polymorphisms A192G of INHA and A-320T of FSHR, and explore the association of the genotypic combinations with milk traits. Materials and methods. 1240 lactations of 356 animals from 9 herds in 6 municipalities of Antioquia were analyzed. Genotyping was performed by PCR-RFLP. Structure and genetic diversity parameters were determined using GenAlex software. The association of genotypes combinations with productive and reproductive traits was explored through a linear mixed model. Results. SNP A192G showed a frequency of 0.534 and 0.466 for A and G alleles respectively and SNP A-320T had a frequency of 0.660 far A allele and 0.339 for T allele, this way the population is in HWE. The F ST, F IS and F IT values were 0.059, 0.285 and 0.328 respectively indicating a moderate genetic differentiation between subpopulations. The A-320T SNP showed significant effect on milk yield. Fat and protein percentage, calving interval and services per conception were not affected by these polymorphisms or their interaction. Conclusions. Phenotypic selection made on this population has not been strong enough to generate noticeable changes in allele frequencies of these polymorphisms or deviations from Hardy-Weinberg equilibrium. The interaction of these polymorphisms has no significant effect on the characteristics of zootechnical interest, so its use in programs of molecular marker assisted selection is not recommended.

Objetivo. Analizar la estructura y diferenciación genética de una población de vacas Holstein de Antioquia a partir de los polimorF ISmos A192G de INHA y A-320T de FSHR, y explorar la asociación de las combinaciones genotípicas con características de importancia económica en lecherías especializadas. Materiales y métodos. Se analizaron 1240 lactancias, de 356 animales de 9 hatos en 6 municipios de Antioquia. La genotipificación se realizó mediante PCR-RFLP. Se determinaron parámetros de estructura y diversidad genética utilizando el software GenAlex. La asociación de las combinaciones de genotipos con características productivas y reproductivas se exploró mediante un modelo linear mixto. Resultados. El SNP A192G presentó una frecuencia de 0.534 y 0.466 para el alelo A y G respectivamente y el SNP A-320T tuvo una frecuencia de 0.660 para el alelo A y 0.339 para el alelo T, encontrándose la población en HWE. Los valores F ST, F IS y F IT fueron 0.059, 0.285 y 0.328 respectivamente indicando una moderada diferenciación genética entre subpoblaciones. El SNP A-320T presentó efecto significativo sobre la producción de leche. El porcentaje de grasa, proteína, intervalo entre partos y servicios por concepción no se vieron afectados por los polimorF ISmos o su interacción. Conclusiones. La selección fenotípica realizada sobre esta población no ha sido lo suficientemente fuerte para generar cambios notorios en las frecuencias alélicas de estos polimorF ISmos ni desviaciones del equilibrio de Hardy-Weinberg. La interacción de estos polimorF ISmos no presenta un efecto significativo sobre las características de interés zootécnico por lo cual no se recomienda su uso en programas de selección asistida por marcadores moleculares.

High genetic diversity and small genetic variation among populations of Magnolia wufengensis (Magnoliaceae), revealed by ISSR and SRAP marker

Background Genetic diversity and genetic variation of 10 populations and subpopulations of Magnolia wufengensis, a new and endangered endemic species, were examined by inter simple sequence repeat (ISSR) and sequence-related amplified polymorphism (SRAP) molecular markers. Compared with other endangered endemic Magnolia taxa, M. wufengensis holds a relatively high level of genetic variation. Result Total genetic diversity was found to be 87.7% for ISSR and 88.0% for SRAP markers. For polymorphic loci (P), the effective mean number of alleles (Ae) was 1.414 for ISSR markers and 1.458 for SRAP markers, while the mean expected heterozygosity (H) was 0.256 using ISSR and 0.291 for SRAP markers. Within-population variation was estimated for P as 74.9% using ISSR and 74.6% with SRAP markers; the number of alleles Ae was 1.379 with ISSR and 1.397 for SRAP and H 0.235 with ISSR and 0.247 for SRAP markers. Conclusion The analysis of molecular variation of both ISSR and SRAP marker systems indicated that most genetic variation is within populations, with values of 90.64% and 82.92% respectively. Mantel tests indicated a moderate association between the two marker systems and a low correlation between genetic and geographic distances. High levels of genetic diversity and low levels of population divergence suggest that genetic drift is not currently of great concern for this species. Severe habitat loss and fragmentation, predominantly ascribed to anthropogenic pressures, caused in-situ developing restriction of this species. Action for conserving this rare species for its long-term survival should be taken immediately.

Fine-scale population genetic structure of Oncomelania hupensis based on microsatellite DNA markers / 中国人兽共患病学报

The genetic structure of small-scale landscape groups of Oncomelania hupensis in Songzi City ,Hubei Province was identify in this study .O .hupensis snails were collected from 10 habitats in Songzi City ,of which 6 polymorphic microsat-ellite DNA loci (T6-17 ,P101 ,D11 ,B14 ,T4-33 ,and C22) were carried out with GeneScan .The number of alleles (Na) ,het-erozygosity (H) ,fixation index (FST) of snails in each group ,genetic distance between groups ,and the polymorphic informa-tion content (PIC) were calculated .Cluster analysis was then carried out based on genetic distance ,and hierarchical AMOVA calculation was conducted .By certified the shells of snails ,10 groups were divided into light and ribbed shell (including shallow rib and deep rib) .There were 141 alleles in total detection on 10 populations and 20-34 alleles in each locus ,which were detec-ted for 23 .5 on average .The average number of alleles in 6 loci was 1 .575 and the number of alleles in each locus was uneven , showing large numerical differences ranged from 0 .445 to 3 .060 .The average observed heterozygosity (Ho) ranged from 0 .438 ue between paired populations was from -0 .015 64 to 0 .252 47 ,and the polymorphic information content in the population ranged from 0 .528 -0 .857 ,showing a high polymorphism .Hierarchical AMOVA calculations showed that inter-individual variation of the snails occupied 88 .4% of the total variations .Cluster analysis revealed that the three ribbed shell population in Munu Kou Village ,Hengti Village and Yixing Village first clustered to the three light shell population in Mashizizu Village , Mingzhu Village and Tuqiao Village ,then clustered to the light shell population in Tuanshan Village and Jiama Cao Village with the two shallow rib population in Desheng Village and Tianmu He Village .Under the different landscape environment of Songzi Area ,there were different shells presenting on the morphology of O .hupensis .Although there was a rich diversity on O .hupensis of Songzi City ,the genetic differences mostly present in individuals .Different groups didn’t show the significant genetic differentiation among the different shell morphology of O .hupensis .

Multilocus sequence typing and its application on population genetic struc-ture analysis of parasites / 中国血吸虫病防治杂志

Multilocus sequence typing MLST with high solution sensitivity and specificity is widely used to study the population genetic structure of pathogen by amplification and sequencing of the housekeeping genes. MLST also provides more evidence and plays an important role in parasite research. This paper reviews the principle and method of MLST and its applica-tion on population genetic structure analysis of parasites.

Estructura genética, ancestralidad y su relación con los estudios en salud humana / Genetic structure, ancestry and their relationship to human health studies

La mezcla entre individuos nativos y múltiples colonos ha dejado como resultado la actual configuración de las poblaciones humanas, lo cual puede conllevar a estructura genética, fenómeno apreciable al observar diferencias en las frecuencias alélicas y genotípicas de las poblaciones de una región geográfica respecto a otra. El análisis de estas poblaciones se ha enfocado en la identificación y cuantificación del grado de mezcla, herramienta útil en la comprobación mediante la asociación de marcadores polimórficos involucrados en el desarrollo de enfermedades. Un obstáculo en la identificación de variantes genéticas asociadas a enfermedades, es la comparación de casos y controles procedentes de poblaciones con diferentes antecedentes genéticos. En este sentido, es importante establecer el grado de estructura genética en las poblaciones debido a la distribución diferencial de los polimorfismos asociados a una enfermedad de interés...

The current configuration of human populations is due to the mix of native individuals and many colonizers; it can entail genetic structure, a phenomenon appreciable to observe differences in allele and genotype frequencies of populations of a geographic region over another. This analysis has focused on the identification and quantification of the degree of mixing, useful tool for checking through association of polymorphic markers involved in the development of diseases. One obstacle in identifying genetic variants associated with diseases is the comparison of cases and controls from populations with different genetic backgrounds. In the opposite sense, it is important to establish the degree of genetic structure in populations due to the differential distribution of alleles of polymorphisms associated with a disease of interest...

Genetic variability in Mediterranean buffalos evaluated by pedigree analysis / Variabilidade genética na raça bubalina Mediterrânea avaliada por meio de análise de pedigree

The objective of this research was to study the population genetic structure of four herds of Mediterranean buffaloes in Brazil. It was used pedigree data from 6,588 buffaloes of Mediterranean breed born from 1980 to 2002. Of the total number of animals studied, 60.5, 15.3 and 2.1% had a pedigree in the first, second and third ascendancy, respectively. The effective number of herds that provided breeding males was 1.60 for parents, 1.16 for grandparents and 1.00 for great-grandparents. There were 923 founder animals and only 71 effective founders. The effective number of ancestors explaining the genetic variability of the population was 71 and only 30 ancestors accounted for 50% of the genetic variability of the population. The average relatedness coefficient (AR) between individuals and inbreeding (F) of the population were estimated at 0.37 and 0.34% respectively. The average estimate of generation interval was 8.71±2.85 years. The variability of the current population is the result of a few ancestors, who are mostly also founders showing that the population was developed from a narrow genetic base which characterizes the occurrence of founder effect.

O objetivo deste trabalho foi estudar a estrutura genética populacional de bubalinos da raça Mediterrâneo, em quatros rebanhos, no Brasil. Foram utilizados dados de pedigree de 6.588 bubalinos da raça Mediterrâneo nascidos no período de 1980 a 2002. Do total de animais estudados, 60,5; 15,3 e 2,1% possuíam pedigree na primeira, segunda e terceira ascendência, respectivamente. O número efetivo de rebanhos que forneceram machos reprodutores foi de 1,60 para pais; 1,16 para avôs e 1,00 para bisavôs. O número de animais fundadores foi 923 e o número efetivo de fundadores foi apenas 71. O número efetivo de ancestrais que explicaram a variabilidade genética da população foi de 71 e somente 30 ancestrais explicaram 50% da variabilidade genética da população. Os coeficientes médios de relação (CR) entre os indivíduos da população e de endogamia (F) foram estimados em 0,37 e 0,34%, respectivamente. A estimativa média do intervalo de gerações foi de 8,71±2,85 anos. A variabilidade da população atual é fruto da contribuição de poucos ancestrais, que são, na sua maioria, também fundadores, evidenciando que a população se desenvolveu a partir de uma base genética estreita, o que caracteriza a ocorrência do efeito fundador.

Variabilidade Genética em Populações de Aedes aegypti (L. ) (Diptera: Culicidae) Utilizando Marcadores de RAPD / Genetic Variability in Aedes aegypti (L. ) (Diptera: Culicidae) Populations Using RAPD Markers

Aedes aegypti (L.) é vetor de importantes doenças como a febre amarela e a dengue, presentes em regiões tropicais e subtropicais. Para o sucesso no seu controle biológico é importante conhecer a estrutura genética e os mecanismos que resultaram na diversidade das populações. O objetivo deste estudo foi analisar a variabilidade genética de diferentes populações de A. aegypti utilizando marcadores de RAPD (Polimorfismo de DNA amplificado ao acaso). DNA de dez larvas coletadas a partir de três populações de diferentes localidades foi analisado usando dez iniciadores de RAPD. Os resultados indicaram a existência de variabilidade genética inter e intrapopulacional. Isso foi confirmado por um dendrograma que agrupou as populações em dois blocos principais com similaridade genética de 24 por cento. Em um desses agrupamentos foi possível distinguir duas populações que apresentaram grau de similaridade de 50 por cento. A diversidade genética entre as populações (55,01 por cento) foi mais elevada que a diversidade genética dentro das populações (44,99 por cento) aplicando-se análise por AMOVA. Altos níveis de polimorfismo genético (Ht = 0.2656) e de diferenciação genética entre as populações (Gst = 0.3689) foram observados. Além disso, o protocolo de extração de DNA adotado mostrou-se eficiente para a análise do inseto independente do seu estágio de desenvolvimento, evitando-se o acréscimo de reagentes ou etapas adicionais de processamento. Futuros experimentos poderão ser realizados para confirmar se a variabilidade observada pode estar ligada às características de resistência de cada população a um determinado pesticida.

Aedes aegypti (L.) is an important vector of diseases such as the yellow fever and dengue, present in tropical and subtropical regions. The objective of this study was to analyze the genetic variability of different A. aegypti populations using RAPD (Random Amplified Polymorphic DNA) markers as a basic study to support the use of biocontrol strategies. DNA of ten collected larvae from three different populations were analyzed using ten RAPD primers. The results indicated the existence of genetic variability inter and intrapopulation. This was confirmed by a dendrogram that grouped the populations in two main clusters with a genetic similarity of 24 percent. In one of these clusters, it was possible to distinguish two populations that showed 50 percent similarity. The molecular variance analysis indicated that the interpopulation genetic diversity (55,01 percent) was higher than the intrapopulation genetic diversity (44,99 percent). A high genetic polymorphism (Ht = 0.2656) and high levels of genetic differentiation between populations (Gst = 0.3689) were found. The adopted DNA extraction protocol proved to be efficient regardless the insect development stage used, avoiding the addition of reagents or additional stages of processing. Future experiments can be performed to confirm if the detected variability is related to the resistance characteristics of each population to a determined pesticide.

Can Lutjanus purpureus (South red snapper) be "legally" considered a red snapper (Lutjanus campechanus)?

Red snappers (Lutjanus purpureus in Brazil and Lutjanus campechanus in USA and Gulf of Mexico) are both under clear effect of overfishing. Because of their high morphological similarity it has already been suggested that they could possibly be considered as a single species. To investigate the degree of similarity and the genetic structure of red snapper populations we constructed a common dataset of partial D-loop mtDNA sequences of L. purpureus from Brazil (Amapá, Pará and Maranhão) and L. campechanus from the Atlantic coast of the USA (Florida, Louisiana and Mississippi). Phylogenetic and population genetic analyses surprisingly depicted high similarity between L. campechanus and L. purpureus, compatible with the hypothesis of a single species of red snapper for the Western Atlantic Ocean. These preliminary but very curious findings open an important discussion regarding the legislation involved on the capture of this overexploited fish resources as well as regarding their taxonomy.

Genetic Variation of Anopheles dirus A and D (Diptera:Culicidae) in China: Inferred by mtDNA-COⅠ Gene Sequences / 中国寄生虫学与寄生虫病杂志

Objective To interpret genetic variation and population structure of Anopheles dirus A and D from China by molecular marker. Methods Samples included An. dirus A of Hainan laboratory colony (n=13), and field specimen from Mengla (n=17) and Jiangcheng (n=17) in Yunnan Province. The specimens were identified by PCR assay before study. mtDNA-COⅠ region was amplified and sequenced. Genetic variation and population structure was estimated according to sequence data. Results The mtDNA-COⅠ gene with a length of 959 bp was analyzed. There were three haplotypes in An. dirus A and six haplotypes in An. dirus D. The above haplotypes distributed in three populations unif-ormly. The average number of pairwise differences within Mengla population (7.441 2) was greater than that of Jiangcheng (1.279 4) and Hainan (1.051 3) populations, which suggested that the level of genetic divergence was the highest within Mengla population. The result of hierarchical AMOVA estimation showed a limited geneflow (Fst=0.799 9), therefore the variation level in a population (20.01%) was smaller than among the populations (79.99%). Conclusion The inter-specific genetic variation between An. dirus A and D in China was small and the level of divergence among individuals was high.