scholarly journals Is it possible to obtain zero estimates of genetic diversity? A case study of the Nigerian indigeneous goat breeds at the β-lactoglobulin gene locus

2017 ◽  
Vol 33 (4) ◽  
pp. 375-388
Author(s):  
Emeka Ezewudo ◽  
Geka Abubakar ◽  
Sunday Egena ◽  
Olushola Alabi
Keyword(s):  
Genetic Diversity ◽  
Genetic Distance ◽  
Gene Locus ◽  
Polymorphic Locus ◽  
Information Index ◽  
Expected Heterozygosity ◽  
Goat Population ◽  
The Mean ◽  
Β Lactoglobulin

The current investigation was conducted to appraise the genetic diversity and genetic distance of three goat populations namely; Red Sokoto, Sahel and West African Dwarf (WAD), in Nigeria, making use of blood samples collected from 20, 20 and 20 individual from which blood DNAs were extraction, respectively. The DNAs extracted were used to study polymorphism at the ?-lactoglobulin gene locus using RLFP-PCR process. Results revealed that the mean total number of alleles was 1 while the effective number of alleles was also 1. The percentage of polymorphic locus was 0% while Shannon?s information index, observed homozygousity, expected heterozygosity, unbiased expected heterozygosity and inbreeding coefficient (F) were all observed to be 0.000. The pairwise Fst was 0.000 between all the breeds of goats. Variation within and between the populations of goats was 0% at p>0.05. The genetic distance between the goat breeds was 0.000. The present study revealed that RLFP-PCR may not be a powerful tool for the study of the ?-lactoglobulin gene locus and hence other methodologies should be employed for a broader judgment on the genetic status of the goat population at the locus.

scholarly journals The Genetic Diversity and Geographic Differentiation of the Wild Soybean in Northeast China Based on Nuclear Microsatellite Variation

2018 ◽  
Vol 2018 ◽  
pp. 1-9
Author(s):  
Hongkun Zhao ◽  
Yumin Wang ◽  
Fu Xing ◽  
Xiaodong Liu ◽  
Cuiping Yuan ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Distance ◽  
Northeast China ◽  
Wild Soybean ◽  
Population Level ◽  
Mantel Test ◽  
Microsatellite Variation ◽  
Information Index ◽  
Ssr Loci ◽  
The Mean

In this study, the genetic diversity and population structure of 205 wild soybean core collections in Northeast China from nine latitude populations and nine longitude populations were evaluated using SSR markers. A total of 973 alleles were detected by 43 SSR loci, and the average number of alleles per locus was 22.628. The mean Shannon information index (I) and the mean expected heterozygosity were 2.528 and 0.879, respectively. At the population level, the regions of 42°N and 124°E had the highest genetic diversity among all latitudes and longitudes. The greater the difference in latitude was, the greater the genetic distance was, whereas a similar trend was not found in longitude populations. Three main clusters (1N, <41°N-42°N; 2N, 43°N-44°N; and 3N, 45°N–>49°N) were assigned to populations. AMOVA analysis showed that the genetic differentiation among latitude and longitude populations was 0.088 and 0.058, respectively, and the majority of genetic variation occurred within populations. The Mantel test revealed that genetic distance was significantly correlated with geographical distance (r=0.207, p<0.05). Furthermore, spatial autocorrelation analysis showed that there was a spatial structure (ω=119.58, p<0.01) and the correlation coefficient (r) decreased as distance increased within a radius of 250 km.

scholarly journals Genetic diversity of different breeds of Kazakh sheep using microsatellite analysis

2019 ◽  
Vol 62 (1) ◽  
pp. 305-312
Author(s):  
Kairat Dossybayev ◽  
Zarina Orazymbetova ◽  
Aizhan Mussayeva ◽  
Naruya Saitou ◽  
Rakhymbek Zhapbasov ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Distance ◽  
Microsatellite Loci ◽  
Allelic Diversity ◽  
Genetic Distances ◽  
Sheep Breed ◽  
Expected Heterozygosity ◽  
The Mean ◽  
High Level ◽  
Short Tandem

Abstract. A total of 75 individuals from five sheep populations in Kazakhstan were investigated based on 12 STR (short tandem repeat, also known as microsatellite) markers in order to study their genetic structure and phylogenetic relationship based on genetic distances. These sheep had a high level of genetic diversity. In total, 163 alleles were found in all the populations using 12 microsatellite loci. The mean number of alleles, effective number of alleles, and polymorphism information content (PIC) values per loci were 13.4, 5.9, and 0.78, respectively. Comparing the allelic diversity between the populations, the highest genetic diversity was observed in the Edilbay-1 sheep breed (8.333±0.644), and the lowest parameter was for Kazakh Arkhar-Merino (7.083±0.633). In all populations, there is a deficiency of heterozygosity. The largest genetic diversity was found in loci INRA023 and CSRD247 with 16 alleles, and the smallest polymorphism was noted for the locus D5S2 with 8 alleles. The level of observed heterozygosity was in the range 0.678±0.051 for Kazakh Arkhar-Merino and 0.767±0.047 for Kazakh fat-tailed coarse wool. The expected heterozygosity level range was from 0.702±0.033 for Kazakh Arkhar-Merino to 0.777±0.023 for Edilbay-1. When 12 microsatellite loci are compared, the OarFCB20 locus showed the highest level of genetic variability. Excess of heterozygosity was observed at three loci; MAF065, McM042, and OarFCB20. The highest genetic distance was observed between Kazakh Arkhar-Merino and Edilbay-1, whereas the genetic distance between Edilbay-1 and Edilbay-2 is the smallest using Nei's standard genetic distance. The Edilbay-1 sheep breed possesses the largest genetic diversity among these five populations.

scholarly journals Isoenzymatic variation in the germplasm of Brazilian races of maize (Zea mays L.)

2000 ◽  
Vol 23 (2) ◽  
pp. 375-380 ◽  
Author(s):  
Marcos Aparecido Gimenes ◽  
Catalina Romero Lopes
Keyword(s):  
Genetic Diversity ◽  
Zea Mays ◽  
Genetic Variability ◽  
Zea Mays L ◽  
Polymorphic Locus ◽  
Maize Breeding ◽  
Breeding Programs ◽  
Expected Heterozygosity ◽  
Total Genetic Diversity ◽  
The Mean

There are more than 200 races of maize (Zea mays L.) divided into three groups (ancient commercial races, the recent commercial races, and indigenous races). Although the indigenous races have no commercial value, they have many important characteristics which can be incorporated into maize breeding programs. Most Brazilian indigenous germplasm race stocks were collected at least 40 years ago, and nothing is known of the genetic variability present in this germplasm. The genetic variability was assayed in 15 populations from four indigenous races of maize (Caingang, Entrelaçado, Lenha and Moroti) and five indigenous cultivars, using five isoenzymatic systems encoded by 14 loci. The analysis revealed a low level of variability among the samples studied. Overall, the mean number of alleles/polymorphic locus was three, 64.3% of the loci analyzed being polymorphic and the estimated heterozygosity was 0.352. The mean number of alleles/polymorphic locus per population was 1.6. A mean of 47.5% of the loci were polymorphic. The mean expected heterozygosity was 0.195, the mean genetic identity was 0.821 and the proportion of total genetic diversity partitioned among populations (Gst) was 0.156. A founder effect could explain the low variability detected.

scholarly journals Genetic Diversity of Populations of Akhal-Teke Horses from the Czech Republic, Russia, Estonia and Switzerland

2016 ◽  
Vol 64 (2) ◽  
pp. 461-466 ◽  
Author(s):  
Iva Jiskrová ◽  
Irena Vrtková ◽  
Michaela Prausová
Keyword(s):  
Genetic Diversity ◽  
Czech Republic ◽  
Genetic Distance ◽  
Genetic Parameters ◽  
Inbreeding Coefficient ◽  
The Other ◽  
Effective Number ◽  
The Czech Republic ◽  
Expected Heterozygosity ◽  
The Mean

Our research objective was to evaluate the genetic parameters in the populations of Akhal-Teke horses in 4 countries: Czech Republic, Russia, Estonia and Switzerland. The experiment involved a total of 325 Akhal-Teke horses; 121 horses came from the Czech Republic, 152 were from Russia, 28 were from Estonia and 24 horses came from Switzerland. For the divided database of micro satellites we evaluated the following parameters: effective number of alleles, frequency of alleles for the groups of horses; the observed heterozygosity (HO); the expected heterozygosity (HE); the inbreeding coefficient (Fis); and the genetic distance. The researched population is polymorphous. The population in the Czech Republic differs from the other three countries in the numbers of alleles per locus. The Czech population also includes Akhal-Teke horses which are not purebred Akhal-Teke horses. A confirmation of this fact is the effective number of alleles. The population in the Czech Republic exhibits the highest mean number of effective alleles. The Akhal-Teke population in Estonia exhibits the highest mean observed heterozygosity. By contrast, the population in the Czech Republic exhibits the lowest mean observed heterozygosity. In the Czech Republic the mean Fis value is a positive number indicating a reduced number of heterozygotes in the Czech Akhal-Teke population. The genetic distance is the highest between populations of horses bred in Russia and Estonia. The genetic distance is the lowest between populations of Akhal-Teke horses bred in Russia and in the Czech Republic.

scholarly journals Genetic diversity revealed by AFLP markers in Albanian goat breeds

2012 ◽  
Vol 64 (2) ◽  
pp. 799-807 ◽  
Author(s):  
Anila Hoda ◽  
Lumturi Sena ◽  
Gentian Hykaj
Keyword(s):  
Genetic Diversity ◽  
Genetic Distance ◽  
Fragment Length Polymorphism ◽  
Similarity Index ◽  
Shannon Index ◽  
Upgma Tree ◽  
Expected Heterozygosity ◽  
The Mean ◽  
High Level ◽  
Aflp Technique

The amplified fragment length polymorphism (AFLP) technique with three EcoRI/TaqI primer combinations was used in 185 unrelated individuals, representative of 6 local goat breeds of Albania, and 107 markers were generated. The mean Nei?s expected heterozygosity value for the whole population was 0.199 and the mean Shannon index was 0.249, indicating a high level of within-breed diversity. Wright?s FST index, Nei?s unbiased genetic distance and Reynolds? genetic distance were calculated. Pairwise Fst values among the populations ranged from 0.019 to 0.047. A highly significant average FST of 0.031 was estimated, showing a low level of breed subdivision. Most of the variation is accounted for by differences among individuals. Cluster analysis based on Reynolds? genetic distance between breeds and PCA were performed. An individual UPGMA tree based on Jaccard?s similarity index showed clusters with individuals from all goat breeds. Analysis of population structure points to a high level of admixture among breeds.

Estimation of Genetic Diversity Among Teressa Goat Population of A and N Islands by using Microsatellite Markers

2020 ◽  
Author(s):  
Jai Sunder ◽  
S. Jeyakumar ◽  
S. P. Yadav ◽  
A. K. De ◽  
A. Kundu ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Microsatellite Markers ◽  
Ex Situ ◽  
Mode Shift ◽  
Information Index ◽  
Goat Population ◽  
Indigenous Goat ◽  
Nicobar Islands ◽  
Sparse Population

Background: Teressa goat is an indigenous goat breed of Andaman and Nicobar Islands. These goats are mainly distributed in the Nicobar group of islands, however, sparse population is also available in the Andaman Islands. In order to understand the genetic diversity and variation among the population of Teressa goat, the studies on the molecular characterization was done by using microsatellite molecular markers. Methods: Randomly a total of 48 blood samples were collected different areas of the Nicobar Islands representing the breeding tract of the Teressa goat. Based on the guidelines of ISAG and FAO, a total of 15 recommended microsatellite markers were selected for the microsatellite analysis study. The data were analysed to study the diversity analysis at each locus by using GENETIX software package. Bottleneck hypothesis was also studied by using BOTTLENECK 1.2.01 and FIS, FIT and FIT values were calculated and heterozygosity deficiency at each locus using FSTAT software. Result: A total of 50 genotypes were observed across the 15 loci. The number of genotype varied between (MAF70; SRCRSP3) 1 and 6 (SRCRSP15). The effective number of alleles (Ne) varied from 2 to 6.98 in Teressa goat. Shannon’s Information Index (I) value was found to be high (1.1856±0.4369), it indicated that the level of diversity among the population of the Teressa goat is high. All the values of FIS obtained were negative which is suggestive of no inbreeding within the populations and the animals were outbred. The mode-shift test indicated the genetic bottleneck in Teressa and needs greater attention towards in situ/ex situ conservation. The present study provides the valuable information about the genetic makeup of the Teressa goat, however, detail study is required to carry out to study the important traits linked with production for further utilization of this breed.

GENIC HETEROZYGOSITY AND PROTEIN POLYMORPHISM AMONG LOCAL POPULATIONS OF OENOTHERA BIENNIS

Genetics ◽  
1975 ◽  
Vol 79 (3) ◽  
pp. 477-491
Author(s):  
Donald A Levin
Keyword(s):  
Genetic Diversity ◽  
Genetic Structure ◽  
Gene Frequency ◽  
Genetic Variance ◽  
Polymorphic Locus ◽  
Cook County ◽  
Oenothera Biennis ◽  
Polymorphic Loci ◽  
Local Populations ◽  
The Mean

ABSTRACT Twenty enzyme loci were studied in 44 Illinois populations of Oenothera biennis; four were polymorphic. Most of the variation was distributed between populations. Fifty-nine percent of the populations had one genotype, 27% two genotypes and the remaining 16% from three to five genotypes; the average was 1.50. The proportion of genetic diversity present in single populations is.38 of that present in the state. Members of single populations were uniformly heterozygous for 1 to 4 loci. The mean heterozygosity per population ranged from 0 to 20%. For Illinois populations collectively, heterozygosity averaged 4.5%. There was much gene frequency heterogeneity between populations. The true standardized genetic variance among populations for alleles at polymorphic loci varied from.40 to.78. Populations from Cook County were much more similar inter se than those downstate, had fewer genotypes and polymorphic loci, and had less heterozygosity than downstate populations. The mean normalized genetic identity among Cook County populations was.987 versus.947 for downstate populations. The mean number of genotypes per population in Cook County was 1.06 versus 2.40 in downstate populations. There was only one polymorphic locus in Cook County, VLP. The genetic structure of Oe. biennis suggests that single populations are colonized by one, or at best a few individuals. Cook County populations are judged to be less variable than downstate populations because the mean age of the populations probably is less than that of those downstate.

Genetic characterization of local goats of Karnataka by microsatellite marker analysis

2018 ◽  
Author(s):  
R. Jayashree ◽  
M. R. Jayashankar ◽  
C. S. Nagaraja ◽  
Isloor Shrikrishna ◽  
K. Satyanarayana
Keyword(s):  
Microsatellite Marker ◽  
Genomic Dna ◽  
Genetic Characterization ◽  
Expected Heterozygosity ◽  
Marker Analysis ◽  
Goat Population ◽  
Pcr Products ◽  
The Mean ◽  
Microsatellite Marker Analysis

The diversity status of local goats of Karnataka was studied by using microsatellite marker analysis. The genomic DNA from unrelated local goats were PCR- amplified with a panel of 23 microsatellite markers. Microsatellite PCR products were multiplexed and run on capillary based genetic analyser and the raw data obtained was analysed. Totally 158 alleles were observed and the number of alleles ranged from three (ILSTS005 and OarJMP29) to 13 (RM088). The number of effective alleles ranged from 2.25 (ILSTS005) to 8.40 (RM088) in all the 23 loci studied. The mean observed heterozygosity (Ho) was 0.4698±0.2214 [range 0 (ETH225) to 0.8462 (ILSTS034)] and the mean expected heterozygosity (He) was 0.7471± 0.1098 [range 0.5656 (ILSTS005) to 0.9138 (SRCRSP 8)] indicating the heterogenous nature of the local goat population of Karnataka.

Genetic structure and proposed conservation strategy for natural populations of Calycanthus chinensis Cheng et S.Y. Chang (Calycanthaceae)

2008 ◽  
Vol 88 (1) ◽  
pp. 179-186 ◽  
Author(s):  
Chu-Chuan Fan ◽  
Nicola Pecchioni ◽  
Long-Qing Chen
Keyword(s):  
Genetic Diversity ◽  
Gene Flow ◽  
Genetic Differentiation ◽  
Genetic Distance ◽  
Gene Diversity ◽  
Genetic Relationships ◽  
Natural Populations ◽  
Population Level ◽  
Conservation Strategy ◽  
Information Index

Calycanthus chinensis Cheng et S.Y. Chang, a tertiary relic species in China, is a shade-loving and deciduous bush withan elegant shape and beautiful flower of high ornamental value. It was widely planted in gardens and miniature scapes in China.The objective of this study was to characterize the genetic variation and structure in the three extant populations of the species, in order to provide useful information for a future conservation strategy. Twenty-two of 120 RAPD primers were selected and a total of 257 stable and clear DNA fragments were scored. Calycanthus chinensis showed a lower level of genetic diversity. At the population level, the percentage of polymorphic loci, Nei's gene diversity and Shannon’s information index were 40.9%, 0.1641 and 0.2386, respectively; while at the species level, the corresponding values were 59.1%, 0.2097 and 0.3123, respectively. The estimates of genetic differentiation based on Shannon’s information index (0.2360), Nei’s gene diversity (0.2175) and AMOVA (24.94%) were very similar, and significantly higher than the average genetic differentiation reported in outcrossed spermatophyte. So it suggested high genetic differentiation emerged among populations of C. chinensis. Genetic relationships among populations were assessed by Nei’s standard genetic distance, which suggested that the Tiantai population was genetically distinct from the other two populations. Moreover, the genetic distance was significantly correlated with geographical distance among populations (r = 0.997, t > t0.05). The gene flow (Nm) was 0.8994, indicating that gene exchange among populations was restricted. A conservation strategy was proposed based on the low gene flow and habitat deterioration, which are contributing to the endangered status of this species. Key words: Genetic diversity, endangered plant, population genetics, RAPD

scholarly journals Genetic Diversity of Tef [Eragrostis tef (Zucc.)Trotter] as Revealed by Microsatellite Markers

2021 ◽  
Vol 2021 ◽  
pp. 1-9
Author(s):  
Mahilet Tadesse ◽  
Mulugeta Kebede ◽  
Dejene Girma
Keyword(s):  
Genetic Diversity ◽  
Polymorphic Information Content ◽  
Mean Value ◽  
Eragrostis Tef ◽  
Human Consumption ◽  
Gene Pools ◽  
Information Index ◽  
Geographical Regions ◽  
The Mean ◽  
High Level

Genetic variability is the fundamental prerequisite of any crop-breeding program to develop superior cultivars. There are about 350 Eragrostis1 species, of which, tef is the only species cultivated for human consumption. Currently, the Ethiopian Biodiversity Institute (EBI) collected over five thousand tef accessions from different geographical regions, diverse in terms of climate and elevation, which are uncharacterized yet. The objective of this study was to evaluate the genetic diversity among 64 tef accessions using 10 selected polymorphic simple sequence repeats (SSRs) markers. A total of 314 alleles were detected with an average of 14.5 alleles per locus and amplicon size ranged from 90 bp–320 bp. The mean value of polymorphic information content (PIC) was 0.87, appearing polymorphic for all loci. The lowest Fst value (0.05) was recorded among the studied tef populations. The mean value of major allele frequency and the number of effective alleles were 0.33 and 3.32, respectively. The mean value of gene flow (Nm) and Shannon’s information index (I) was 4.74 and 1.65, respectively. The observed (Ho) and expected (He) heterozygosities varied from 0.34 to 0.56 and from 0.58 to 0.76, respectively. The cluster analysis has grouped the 64 tef accessions into three distinct clusters based on their similarity. The PCoA analysis showed that clustering is basing on the geographical origin of accessions. Analysis of molecular variance revealed 56%, 39% and 5% of the total variation due to variation within populations, among individuals and among populations, respectively. Structure bar-plot also inferred three gene pools, but with high level of admixtures. Thus, the present study shows that the identified tef accessions could be of great interest for the initiation of a planned breeding and conservation programs.

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