Molecular variation of Trypanosoma brucei subspecies as revealed by AFLP fingerprinting

Parasitology ◽  
2002 ◽  
Vol 124 (4) ◽  
pp. 349-358 ◽  
Author(s):  
E. E. C. AGBO ◽  
P. A. O. MAJIWA ◽  
H. J. H. M. CLAASSEN ◽  
M. F. W. TE PAS

Genetic analysis of Trypanosoma spp. depends on the detection of variation between strains. We have used the amplified fragment length polymorphism (AFLP) technique to develop a convenient and reliable method for genetic characterization of Trypanosome (sub)species. AFLP accesses multiple independent sites within the genome and would allow a better definition of the relatedness of different Trypanosome (sub)species. Nine isolates (3 from each T. brucei subspecies) were tested with 40 AFLP primer combinations to identify the most appropriate pairs of restriction endonucleases and selective primers. Primers based on the recognition sequences of EcoRI and BglII were chosen and used to analyse 31 T. brucei isolates. Similarity levels calculated with the Pearson correlation coefficient ranged from 15 to 98%, and clusters were determined using the unweighted pair-group method using arithmetic averages (UPGMA). At the intraspecific level, AFLP fingerprints were grouped by numerical analysis in 2 main clusters, allowing a clear separation of T. b. gambiense (cluster I) from T. b. brucei and T. b. rhodesiense isolates (cluster II). Interspecies evaluation of this customized approach produced heterogeneous AFLP patterns, with unique genetic markers, except for T. evansi and T. equiperdum, which showed identical patterns and clustered together.

2008 ◽  
Vol 133 (4) ◽  
pp. 593-597 ◽  
Author(s):  
Salih Kafkas ◽  
Mustafa Özgen ◽  
Yıldız Doğan ◽  
Burcu Özcan ◽  
Sezai Ercişli ◽  
...  

Mulberries (Morus L.) show a great deal of genetic variability and adaptability to various environments. There are more than 24 species of mulberries in cultivated and wild forms. In Turkey, three Morus species, M. alba L., M. nigra L., and M. rubra L., are grown. In this study, we attempted to characterize 43 Morus accessions originating from distinct regions of Turkey using fluorescent dye amplified fragment length polymorphism (AFLP) markers and capillary electrophoresis. The accessions belonged to M. alba, M. nigra, and M. rubra; M. alba consisted of white- and purple-fruited samples. Eight primer combinations generated a total of 416 bands, 337 of which were polymorphic (80.5%). Resolving powers of the AFLP primers ranged from 0.410 to 0.942 making a total of 5.015, whereas the polymorphic information content ranged from 0.662 to 0.898 with an average of 0.812. Unweighted pair-group method of arithmetic mean (UPGMA) clustering of the accessions showed three major groups representing M. nigra, M. rubra, and M. alba accessions. The M. alba group had two subgroups that were not correlated with fruit color. The UPGMA dendrogram of average taxonomic differences confirmed these results. The principle coordinate analysis demonstrated that M. nigra accessions had limited genetic variation. In conclusion, our study indicated that M. nigra and M. rubra are molecularly distinct from M. alba. Our results also suggest that M. nigra accessions having a low level of morphological variation are molecularly similar.


Plant Disease ◽  
2021 ◽  
Author(s):  
Marwa Laribi ◽  
Alireza Akhavan ◽  
Sarrah M'Barek ◽  
Amor Yahyaoui ◽  
Stephen Ernest Strelkov ◽  
...  

Pyrenophora tritici-repentis (Ptr) causes tan spot, an important foliar disease of wheat. A collection of Ptr isolates from Tunisia, located in one of the main secondary centers of diversification of durum wheat, was tested for phenotypic race classification based on virulence on a host differential set, and for the presence of the necrotrophic effector (NE) genes ToxA, ToxB , and toxb by PCR analysis. While races 2, 4, 5, 6, 7, and 8 were identified according to their virulence phenotypes, PCR testing indicated the presence of ‘atypical’ isolates that induced necrosis on the wheat differential ‘Glenlea’, but lacked the expected ToxA gene, suggesting the involvement of other NEs in the Ptr/wheat interaction. Genetic diversity and the Ptr population structure were explored further by examining 59 Tunisian isolates and 35 isolates from Algeria, Azerbaijan, Canada, Iran, and Syria using 24 simple sequence repeat markers. Average genetic diversity, overall gene flow and percentage polymorphic loci were estimated as 0.58, 2.09 and 87%, respectively. Analysis of molecular variance showed that 81% of the genetic variance occurred within populations and 19% between populations. Cluster analysis by the unweighted pair group method indicated that ToxB- isolates grouped together and were distantly related to ToxB+ isolates. Based on Nei’s analysis, the global collection clustered into two distinct groups according to their region of origin. The results suggest that both geographic origin and the host-specificity imposed by different NEs can lead to differentiation among Ptr populations.


2012 ◽  
Vol 22 (1) ◽  
pp. 51-58 ◽  
Author(s):  
M.E. Hoque ◽  
M.M. Hasan

Random Amplified Polymorphic DNA (RAPD) markers were used to study the molecular genetic diversity analysis among six BARI released lentil varieties viz. BARI masur-1, BARI masur-2, BARI masur-3, BARI masur-4, BARI masur-5 and BARI masur-6. PCR amplified products were visualized on 1.0% agarose gel and the band for each primer were scored. Ten RAPD markers were used in this study. Out of them 7 primers showed amplification of 53 DNA fragments with 60.37% of them being polymorphic. The highest number of polymorphic loci was noticed in the variety BARI masur-3. The same variety also showed maximum Nei’s gene diversity value (0.0552). The highest Nei’s genetic distance (0.5002) was observed in BARI masur-1 vs. BARI masur-5 whereas, the lowest genetic distance (0.0692) was found in BARI masur-1 vs. BARI masur-2. The unweighted pair group method of arithmetic mean (UPGMA) dendrogram based on Nei’s genetic distance grouped the six cultivars into two main clusters. BARI masur-1, BARI masur-2 and BARI masur-3 were in cluster I and BARI masur-4, BARI masur-5 and BARI masur-6 were in cluster II. The cultivar BARI masur-4 was closest to the cultivar BARI masur-6 with the lowest genetic distance (0.0972) and the highest genetic distance (0.5002) was found between BARI masur-1 and BARI masur-5. The RAPD markers were found to be useful in molecular characterization of lentil varieties which could be utilized by the breeders for the improvement of lentil cultivars. DOI: http://dx.doi.org/10.3329/ptcb.v22i1.11260 Plant Tissue Cult. & Biotech. 22(1): 51-58, 2012 (June)


2010 ◽  
Vol 20 (1) ◽  
pp. 91-99
Author(s):  
R. C. Jena ◽  
K. C. Samal ◽  
P. K. Chand ◽  
B. K. Das

Randomly amplified polymorphic DNA (RAPD) markers were used for the genetic variation and relationship analysis among 12 Mango (Mangifera indica L.) germplasm. Five oligonucleotide primers were employed to amplify DNA from 12 cultivars. PCR amplification with five primers generated 45 reproducible, clear and distinct bands, out of which 41 bands are considered polymorphic and the remaining four fragments (8.88%)  monomorphic. The size of amplified product ranged from 200 (RPI-5) to 3000 base pairs (RPI-1) with an average of nine bands per primer. The average polymorphism in all the 12 cultivars using the five primers was found to be 91.91%. Among all the primers RPI-2 and RPI-4 have shown 100% polymorphism while RPI-5 was found to be least polymorphism (81.81%). One specific band, namely was found with RPI-5, in a particular variety, Chiratpuri. The UPGMA (Unweighted Pair Group Method of Arithmetic Mean) dendrogram based on Jaccard’s similarity coefficient segregated the 12 mango germplasm into two clusters. Langra, Chiratpuri, Pravasankar, Alphanso, Sindhu and Kesar formed one cluster and rest six mango germplasm grouped together into another cluster. Sindhu and Alphanso cultivar pair was very close to each other with highest similarity coefficient (0.78), which was comparatively higher than all other cultivar pairs. On the other hand, Pravasankar and Neelam cultivar pair was more distinct to each other with the lowest intervarietal similarity coefficient 0.38. This study showed clearly that cultivars from Orissa unveiled maximum diversity and indicated the potential of RAPD markers for the identification of management of mango germplasm for breeding purposes.  Key words: Molecular characterization, Mango germplasm, Dversity  D.O.I. 10.3329/ptcb.v20i1.5972 Plant Tissue Cult. & Biotech. 20(1): 91-99, 2010 (June)


2001 ◽  
Vol 91 (10) ◽  
pp. 973-980 ◽  
Author(s):  
K. H. Lamour ◽  
M. K. Hausbeck

Phytophthora capsici isolates were recovered from pepper and cucurbit hosts at seven locations in Michigan from 1998 to 2000. Isolates were characterized for compatibility type (CT), mefenoxam sensitivity (MS), and amplified fragment length polymorphism (AFLP) marker profiles. In total, 94 AFLP bands were resolved. Individual populations were highly variable. Within populations, 39 to 49% of the AFLP bands were polymorphic and estimated heterozygosities ranged from 0.16 to 0.19. Of the 646 isolates fingerprinted, 70% (454) had unique AFLP profiles. No clones were recovered between years or locations. Pairwise F statistics (ΦST) between populations from different locations ranged from 0.18 to 0.40. A tree based on unweighted pair-group method with arithmetic average cluster analysis indicates discrete clusters based on location. Isolates from the same location showed no clustering based on the year of sampling. Analysis of molecular variance partitioned variability among (40%) and within populations (60%). The overall estimated ΦST was 0.34 (SD = 0.03). A1/A2 CT ratios were ≈1:1, and MS frequencies were similar between years for the two locations sampled over time. These data suggest that P. capsici persists in discrete outcrossing populations and that gene flow among locations in Michigan is infrequent.


2000 ◽  
Vol 78 (10) ◽  
pp. 1845-1854 ◽  
Author(s):  
Mark P Miller ◽  
Larry E Stevens ◽  
Joseph D Busch ◽  
Jeff A Sorensen ◽  
Paul Keim

The Kanab ambersnail (Oxyloma haydeni kanabensis) is a federally endangered mollusc currently known to reside in two locations in the southwestern U.S.A. To determine the extent of within- and between-population genetic variation of this taxon, the amplified fragment length polymorphism (AFLP) technique was used to generate 110 genetic markers among individuals sampled from the two Kanab ambersnail populations and from the only two known southwestern populations of the Niobrara ambersnail (Oxyloma haydeni haydeni) in Utah and northern Arizona. Additional information was obtained from sequence data of cytochrome b and cytochrome oxidase I gene fragments. Results suggest high levels of differentiation among populations, as evidenced through the application of UPGMA (unweighted pair-group method with arthimetic averaging) clustering, F statistics, and Fisher's exact test. Various levels of within-population genetic diversity were observed among populations. Expected heterozygosities ranged from 0.239 to 0.086 under a model assuming Hardy-Weinberg genotypic proportions and ranged from 0.205 to 0.061 under an obligate-selfing completely homozygous model. Results from cluster analyses showed that one Kanab ambersnail population and one Niobrara ambersnail population were more similar than the two Kanab ambersnail populations studied (supported by >80% of bootstrap replicates). These findings were further supported through the phylogenetic analysis of both mito chondrial gene fragments. The data suggest that taxonomic designations need revision, an act that will likely affect the protected status of some of the populations.


2009 ◽  
Vol 134 (4) ◽  
pp. 428-434 ◽  
Author(s):  
Salih Kafkas ◽  
Sezai Ercişli ◽  
Yıldız Doğan ◽  
Yaşar Ertürk ◽  
Ayhan Haznedar ◽  
...  

Individuals in most countries around the world drink tea (Camellia sinensis). Tea drinking has attained ceremonial status in many places as a social and medicinal beverage. Although tea is of great importance in Turkey's economy, little is known about the pattern of genetic variation among the various tea genotypes grown in Turkey. A total of 32 tea genotypes found at the Ataturk Tea and Horticulture Research Institute in the eastern Black Sea region of Turkey were sampled. Fluorescent dye amplified fragment length polymorphism (AFLP) markers and capillary electrophoresis were applied for molecular characterization. The AFLP analysis with six primer combinations generated 835 fragments of which 567 were polymorphic, corresponding to 69.8% polymorphism. Resolving powers of the AFLP primers ranged from 62.6 to 81.9, yielding a total of 437.8; the polymorphic information content (PIC) ranged from 0.76 to 0.83, with an average of 0.79. Genetic similarity values ranged from 0.68 to 0.92, with an average of 0.76. The dendrogram derived by unweighted pair group method with arithmetic mean algorithm (UPGMA) and principal coordinate analysis (PCoA) revealed that all tea genotypes could be clearly divided into four distinct clusters. The results of this study will provide valuable information to the tea cultivar breeding program for the purpose of parental selection.


Sign in / Sign up

Export Citation Format

Share Document