scholarly journals Genetic diversity and population structure of Plasmodium falciparum in Nigeria: insights from microsatellite loci analysis

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Fehintola V. Ajogbasile ◽  
Adeyemi T. Kayode ◽  
Paul E. Oluniyi ◽  
Kazeem O. Akano ◽  
Jessica N. Uwanibe ◽  
...  

Abstract Background Malaria remains a public health burden especially in Nigeria. To develop new malaria control and elimination strategies or refine existing ones, understanding parasite population diversity and transmission patterns is crucial. Methods In this study, characterization of the parasite diversity and structure of Plasmodium falciparum isolates from 633 dried blood spot samples in Nigeria was carried out using 12 microsatellite loci of P. falciparum. These microsatellite loci were amplified via semi-nested polymerase chain reaction (PCR) and fragments were analysed using population genetic tools. Results Estimates of parasite genetic diversity, such as mean number of different alleles (13.52), effective alleles (7.13), allelic richness (11.15) and expected heterozygosity (0.804), were high. Overall linkage disequilibrium was weak (0.006, P < 0.001). Parasite population structure was low (Fst: 0.008–0.105, AMOVA: 0.039). Conclusion The high level of parasite genetic diversity and low population structuring in this study suggests that parasite populations circulating in Nigeria are homogenous. However, higher resolution methods, such as the 24 SNP barcode and whole genome sequencing, may capture more specific parasite genetic signatures circulating in the country. The results obtained can be used as a baseline for parasite genetic diversity and structure, aiding in the formulation of appropriate therapeutic and control strategies in Nigeria.

2020 ◽  
Author(s):  
Fehintola Victoria Ajogbasile ◽  
Adeyemi T. Kayode ◽  
Kazeem O. Akano ◽  
Paul E. Oluniyi ◽  
Jessica N. Uwanibe ◽  
...  

Abstract BackgroundMalaria remains a public health burden especially in Nigeria. To develop new malaria control and elimination strategies or refine existing ones, understanding parasite population diversity and transmission patterns is crucial. MethodsIn this study, we characterized parasite diversity and structure of Plasmodium falciparum isolates from 633 dried blood spot samples in Nigeria, using 12 microsatellite loci of P. falciparum. These microsatellites were amplified via semi-nested polymerase chain reaction (PCR) and fragments were analyzed using GeneMapper and GENALEX 6.5.ResultsEstimates of parasite diversity such as Mean complexity of infection (range: 1.71-2.66) and Expected heterozygosity (range: 0.76-0.82) were high, while parasite population sub-structuring was low (Analysis of molecular variance= 0.039, Fixation index= 0.038 and Linkage disequilibrium= 0.0219). Conclusion We conclude that the high level of genetic diversity and low population structuring in this study suggests that parasite populations circulating in Nigeria are homogenous. This implies that a uniform control strategy will be effective across the six geographical zones of Nigeria. The results obtained can be used as a baseline for parasite diversity and structure, aiding in the formulation of appropriate therapeutic and control strategies in Nigeria.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Minh Cuong Duong ◽  
Oanh Kieu Nguyet Pham ◽  
Phong Thanh Nguyen ◽  
Van Vinh Chau Nguyen ◽  
Phu Hoan Nguyen

Abstract Background Drug-resistant falciparum malaria is an increasing public health burden. This study examined the magnitude of Plasmodium falciparum infection and the patterns and predictors of treatment failure in Vietnam. Methods Medical records of all 443 patients with malaria infection admitted to the Hospital for Tropical Diseases between January 2015 and December 2018 were used to extract information on demographics, risk factors, symptoms, laboratory tests, treatment, and outcome. Results More than half (59.8%, 265/443, CI 55.1–64.4%) of patients acquired Plasmodium falciparum infection of whom 21.9% (58/265, CI 17.1–27.4%) had severe malaria, while 7.2% (19/265, CI 4.6–10.9%) and 19.2% (51/265, CI 14.7–24.5%) developed early treatment failure (ETF) and late treatment failure (LTF) respectively. Among 58 patients with severe malaria, 14 (24.1%) acquired infection in regions where artemisinin resistance has been documented including Binh Phuoc (11 patients), Dak Nong (2 patients) and Gia Lai (1 patient). Under treatment with intravenous artesunate, the median (IQR) parasite half-life of 11 patients coming from Binh Phuoc was 3 h (2.3 to 8.3 h), two patients coming from Dak Nong was 2.8 and 5.7 h, and a patient coming from Gia Lai was 6.5 h. Most patients (98.5%, 261/265) recovered completely. Four patients with severe malaria died. Severe malaria was statistically associated with receiving treatment at previous hospitals (P < 0.001), hepatomegaly (P < 0.001) and number of inpatient days (P < 0.001). Having severe malaria was a predictor of ETF (AOR 6.96, CI 2.55–19.02, P < 0.001). No predictor of LTF was identified. Conclusions Plasmodium falciparum remains the prevalent malaria parasite. Despite low mortality rate, severe malaria is not rare and is a significant predictor of ETF. To reduce the risk for ETF, studies are needed to examine the effectiveness of combination therapy including parenteral artesunate and a parenteral partner drug for severe malaria. The study alerts the possibility of drug-resistant malaria in Africa and other areas in Vietnam, which are known as non-endemic areas of anti-malarial drug resistance. A more comprehensive study using molecular technique in these regions is required to completely understand the magnitude of drug-resistant malaria and to design appropriate control strategies.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Runglawan Chawengkirttikul ◽  
Witchuta Junsiri ◽  
Amaya Watthanadirek ◽  
Napassorn Poolsawat ◽  
Sutthida Minsakorn ◽  
...  

AbstractLeucocytozoon sabrazesi is the intracellular protozoa of leucocytozoonosis, which is transmitted by the insect vectors and affects chickens in most subtropical and tropical regions of the globe, except South America, and causing enormous economic losses due to decreasing meat yield and egg production. In this study, L. sabrazesi gametocytes have been observed in the blood smears, and molecular methods have been used to analyse the occurrence and genetic diversity of L. sabrazesi in blood samples from 313 chickens raised in northern, western and southern parts of Thailand. The nested polymerase chain reaction (nested PCR) assay based on the cytb gene revealed that 80.51% (252/313) chickens were positive of L. sabrazesi. The phylogenetic analysis indicated that L. sabrazesi cytb gene is conserved in Thailand, showed 2 clades and 2 subclades with similarity ranged from 89.5 to 100%. The diversity analysis showed 13 and 18 haplotypes of the sequences from Thailand and from other countries, respectively. The entropy analyses of nucleic acid sequences showed 26 high entropy peaks with values ranging from 0.24493 to 1.21056, while those of amino acid sequences exhibited 5 high entropy peaks with values ranging from 0.39267 to 0.97012. The results; therefore, indicate a high molecular occurrence of L. sabrazesi in chicken blood samples with the associated factors that is statistically significant (p < 0.05). Hence, our results could be used to improve the immunodiagnostic methods and to find appropriate preventive control strategies or vaccination programs against leucocytozoonosis in order to mitigate or eliminate the harmful impact of this infection on chicken industry.


2021 ◽  
Author(s):  
Varun Hiremath ◽  
Kanwar Pal Singh ◽  
Neelu Jain ◽  
Kishan Swaroop ◽  
Pradeep Kumar Jain ◽  
...  

Abstract Genetic diversity and structure analysis using molecular markers is necessary for efficient utilization and sustainable management of gladiolus germplasm. Genetic analysis of gladiolus germplasm using SSR markers is largely missing due to scarce genomic information. In the present investigation, we report 66.66% cross transferability of Gladiolus palustris SSRs whereas 48% of Iris EST-SSRs were cross transferable across the gladiolus genotypes used in the study. A total of 17 highly polymorphic SSRs revealed a total 58 polymorphic loci ranging from two to six in each locus with an average of 3.41 alleles per marker. PIC values ranged from 0.11 to 0.71 with an average value of 0.48. Four SSRs were selectively neutral based on Ewens-Watterson test. Analysis of genetic structure of 84 gladiolus genotypes divided whole germplasm into two subpopulations. 35 genotypes were assigned to subpopulation 1 whereas 37 to subpopulation 2 and rest of the genotypes recorded as admixture. Analysis of molecular variance indicated maximum variance (53.59%) among individuals within subpopulations whereas 36.55% of variation observed among individuals within total population. Least variation (9.86%) was noticed between two subpopulations. Moderate (FST = 0.10) genetic differentiation of two subpopulations was observed. Grouping pattern of population structure was consistent with UPGMA dendrogram based on simple matching dissimilarity coefficient (ranged from 01.6 to 0.89) and PCoA. Genetic relationships assessed among the genotypes of respective clusters assist the breeders in selecting desirable parents for crossing. SSR markers from present study can be utilized for cultivar identification, conservation and sustainable utilization of gladiolus genotypes for crop improvement.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10348
Author(s):  
Austin S. Chipps ◽  
Amanda M. Hale ◽  
Sara P. Weaver ◽  
Dean A. Williams

There are increasing concerns regarding bat mortality at wind energy facilities, especially as installed capacity continues to grow. In North America, wind energy development has recently expanded into the Lower Rio Grande Valley in south Texas where bat species had not previously been exposed to wind turbines. Our study sought to characterize genetic diversity, population structure, and effective population size in Dasypterus ega and D. intermedius, two tree-roosting yellow bats native to this region and for which little is known about their population biology and seasonal movements. There was no evidence of population substructure in either species. Genetic diversity at mitochondrial and microsatellite loci was lower in these yellow bat taxa than in previously studied migratory tree bat species in North America, which may be due to the non-migratory nature of these species at our study site, the fact that our study site is located at a geographic range end for both taxa, and possibly weak ascertainment bias at microsatellite loci. Historical effective population size (NEF) was large for both species, while current estimates of Ne had upper 95% confidence limits that encompassed infinity. We found evidence of strong mitochondrial differentiation between the two putative subspecies of D. intermedius (D. i. floridanus and D. i. intermedius) which are sympatric in this region of Texas, yet little differentiation using microsatellite loci. We suggest this pattern is due to secondary contact and hybridization and possibly incomplete lineage sorting at microsatellite loci. We also found evidence of some hybridization between D. ega and D. intermedius in this region of Texas. We recommend that our data serve as a starting point for the long-term genetic monitoring of these species in order to better understand the impacts of wind-related mortality on these populations over time.


2009 ◽  
Vol 8 (1) ◽  
pp. 155 ◽  
Author(s):  
Tepanata Pumpaibool ◽  
Céline Arnathau ◽  
Patrick Durand ◽  
Naowarat Kanchanakhan ◽  
Napaporn Siripoon ◽  
...  

2013 ◽  
Vol 4 (1) ◽  
pp. 134-138 ◽  
Author(s):  
Kristy Deiner ◽  
Joshua M. Hull ◽  
Bernie May

Abstract We developed primer sets for eight di-, tri-, and tetranucleotide microsatellite loci for the threatened vernal pool fairy shrimp Branchinecta lynchi from CA, CAA, ATG, CAGA, and TAGA enriched genomic libraries. We tested primers in 74 individuals of B. lynchi from California, as well as 19 individuals from six other Branchinecta species: B. coloradensis, B. constricta, B. dissimilis, B. lindahli, B. mesovalensis, and B. oriena. The eight loci showed sufficient variability for investigations of B. lynchi evolution, population structure, and genetic diversity and may provide a new tool for assisting in delineation of management areas.


2019 ◽  
Vol 85 (20) ◽  
Author(s):  
Moein Khojasteh ◽  
S. Mohsen Taghavi ◽  
Pejman Khodaygan ◽  
Habiballah Hamzehzarghani ◽  
Gongyou Chen ◽  
...  

ABSTRACT This study provides a phylogeographic insight into the population diversity of Xanthomonas translucens strains causing bacterial leaf streak disease of small-grain cereals in Iran. Among the 65 bacterial strains isolated from wheat, barley, and gramineous weeds in eight Iranian provinces, multilocus sequence analysis and typing (MLSA and MLST) of four housekeeping genes (dnaK, fyuA, gyrB, and rpoD), identified 57 strains as X. translucens pv. undulosa, while eight strains were identified as X. translucens pv. translucens. Although the pathogenicity patterns on oat and ryegrass weed species varied among the strains, all X. translucens pv. undulosa strains were pathogenic on barley, Harding’s grass, rye (except for XtKm35) and wheat, and all X. translucens pv. translucens strains were pathogenic on barley and Harding’s grass, while none of the latter group was pathogenic on rye or wheat (except for XtKm18). MLST using the 65 strains isolated in Iran, as well as the sequences of the four genes from 112 strains of worldwide origin retrieved from the GenBank database, revealed higher genetic diversity (i.e., haplotype frequency, haplotype diversity, and percentage of polymorphic sites) among the Iranian population of X. translucens than among the North American strains of the pathogen. High genetic diversity of the BLS pathogen in Iran was in congruence with the fact that the Iranian Plateau is considered the center of origin of cultivated wheat. However, further studies using larger collections of strains are warranted to precisely elucidate the global population diversity and center of origin of the pathogen. IMPORTANCE Bacterial leaf streak (BLS) of small-grain cereals (i.e., wheat and barley) is one of the economically important diseases of gramineous crops worldwide. The disease occurs in many countries across the globe, with particular importance in regions characterized by high levels of precipitation. Two genetically distinct xanthomonads—namely, Xanthomonas translucens pv. undulosa and X. translucens pv. translucens—have been reported to cause BLS disease on small-grain cereals. As seed-borne pathogens, the causal agents are included in the A2 list of quarantine pathogens by the European and Mediterranean Plant Protection Organization (EPPO). Despite its global distribution and high economic importance, the population structure, genetic diversity, and phylogeography of X. translucens remain undetermined. This study, using MLSA and MLST, provides a global-scale phylogeography of X. translucens strains infecting small-grain cereals. Based on the diversity parameters, neutrality indices, and population structure, we observe higher genetic diversity of the BLS pathogen in Iran, which is geographically close to the center of origin of common wheat, than has so far been observed in other areas of the world, including North America. The results obtained in this study provide a novel insight into the genetic diversity and population structure of the BLS pathogen of small-grain cereals on a global scale.


2017 ◽  
Vol 16 (3) ◽  
pp. 284-287
Author(s):  
Bruno C. Rossini ◽  
Mariá B. Kampa ◽  
Celso L. Marino ◽  
Fernanda Bortolanza Pereira ◽  
Fábio M. Alves ◽  
...  

AbstractIn this study, we isolate and analyse a new set of microsatellite loci for Cattleya walkeriana. Twenty-two primer pairs were screened for C. walkeriana (n = 32) and assessed for their transferability to Cattleya loddigesii (n = 12) and Cattleya nobilior (n = 06). All loci amplified for C. walkeriana; however, for C. loddigesii and C. nobilior, four and five primers, respectively, did not present amplification. The polymorphic loci presented between 2 and 13 alleles per locus for both C. walkeriana and C. loddigesii, with respective averages of 5.1 and 4.2. For C. nobilior, we found between two and five alleles per locus, with an average of 2.6. For C. walkeriana, observed heterozygosity varied from 0.100 to 0.966, whereas expected heterozygosity ranged from 0.097 to 0.900. The observed and expected heterozygosity for C. loddigesii and C. nobilior were also estimated. We found no significant linkage disequilibrium between any pair of loci, and evidence of null alleles at four loci (Cw16, Cw24, Cw30 and Cw31) for C. walkeriana. The combined power to exclude the first parent and combined non-exclusion probability of identity were 0.999 and 2.3 × 10−20, respectively. These new loci can be used in studies of germplasm resources, and assessments of genotypic and genetic diversity and population structure, thus improving the accuracy of such analyses and their applicability in the conservation and protection of these endangered species.


AoB Plants ◽  
2019 ◽  
Vol 11 (4) ◽  
Author(s):  
Alice Backes ◽  
Geraldo Mäder ◽  
Caroline Turchetto ◽  
Ana Lúcia Segatto ◽  
Jeferson N Fregonezi ◽  
...  

Abstract Different genetic patterns have been demonstrated for narrowly distributed taxa, many of them linking rarity to evolutionary history. Quite a few species in young genera are endemics and have several populations that present low variability, sometimes attributed to geographical isolation or dispersion processes. Assessing the genetic diversity and structure of such species may be important for protecting them and understanding their diversification history. In this study, we used microsatellite markers and plastid sequences to characterize the levels of genetic variation and population structure of two endemic and restricted species that grow in isolated areas on the margin of the distribution of their respective genera. Plastid and nuclear diversities were very low and weakly structured in their populations. Evolutionary scenarios for both species are compatible with open-field expansions during the Pleistocene interglacial periods and genetic variability supports founder effects to explain diversification. At present, both species are suffering from habitat loss and changes in the environment can lead these species towards extinction.


Sign in / Sign up

Export Citation Format

Share Document