Ashraf Ullah - Academia.edu (original) (raw)
Uploads
Papers by Ashraf Ullah
DNA fingerprinting using genetic markers such as Random Amplification of Polymorphic DNA (RAPD),... more DNA fingerprinting using genetic markers such as Random Amplification of Polymorphic DNA (RAPD), Restriction Fragment Length Polymorphism (RFLP), microsatellite (Simple sequence repeat), Amplified Fragment Length Polymorphism (AFLP) etc. can be successfully used to reveal genetic variation within and among different populations.
Genetic characterization of the base population of a breeding program is useful in monitoring cha... more Genetic characterization of the base population of a breeding program is useful in monitoring changes in the genetic structure that might occur over generations. By using microsatellite DNA markers, we have analyzed the genetic population structure of the Jamuna, Padma and Halda river samples of Catla catla maintained in a Brood bank of the Department of Fisheries, Bangladesh. We detected a total of 27 alleles at five loci in 90 individuals with an average of 5.4 alleles per locus. The mean allelic richness of the Jamuna, Padma and the Halda population of catla were 4.800, 5.200, and 4.400, respectively. The average observed (Ho) and expected (He) heterozygosity values for the Jamuna, Padma and the Halda rivers were 0.720, 0.720 and 0.667 and 0.663, 0.678 and 0.643, respectively. The FIS values ranged from -0.341 to 0.121 and found to be nonsignificant while the pairwise FST values ranged from 0.0142 to 0.0507 and found to be significant. The genetic variations in the Jamuna and the Padma populations are comparable and slightly higher than that of the Halda population. Our study detected an excess of heterozygosity indicating recent genetic bottlenecks in the brood bank founder stocks of C. catla.
Key words: Microsatellite, population structure, bottleneck, assignment, family reconstruction.
The founder stock of a captive breeding program is prone to changes in genetic structure due to i... more The founder stock of a captive breeding program is prone to changes in genetic structure due to inbreeding and genetic drift. Genetic characterization of the founder population using suitable molecular markers may help monitor periodic changes in the genetic structure in future. To develop benchmark information about the genetic structure we analyzed six microsatellite loci in the Brodbank collections of rohu (Labeo rohita) originated from three major rivers—the Jamuna, the Padma and the Halda. A total of 28 alleles were detected in 90 individuals with an average of 4.6 alleles per locus. The average observed heterozygosity ranged from 0.655 to 0.705 and the expected heterozygosity ranged from 0.702 to 0.725. The mean FIS values were 0.103, 0.106 and 0.018 for the Jamuna, Padma and Halda fishes respectively. The population pair-wise FST values ranged from 0.0057 to 0.0278. Structure analysis grouped the fishes of the three rivers into two clusters. The numbers of half-sib families were 5, 5 and 4 and the numbers of full-sib families were 12, 10 and 18 for the Halda, Jamuna and the Padma samples respectively. Bottleneck was detected in all the river samples. We recommend to collect more fish from different locations of the major rivers to broaden the genetic variability of the founder stocks of the Brood bank. Keywords: Microsatellite, Genetic variation, Major carps, Brood bank, Bottleneck, Sib-ship
DNA fingerprinting using genetic markers such as Random Amplification of Polymorphic DNA (RAPD),... more DNA fingerprinting using genetic markers such as Random Amplification of Polymorphic DNA (RAPD), Restriction Fragment Length Polymorphism (RFLP), microsatellite (Simple sequence repeat), Amplified Fragment Length Polymorphism (AFLP) etc. can be successfully used to reveal genetic variation within and among different populations.
Genetic characterization of the base population of a breeding program is useful in monitoring cha... more Genetic characterization of the base population of a breeding program is useful in monitoring changes in the genetic structure that might occur over generations. By using microsatellite DNA markers, we have analyzed the genetic population structure of the Jamuna, Padma and Halda river samples of Catla catla maintained in a Brood bank of the Department of Fisheries, Bangladesh. We detected a total of 27 alleles at five loci in 90 individuals with an average of 5.4 alleles per locus. The mean allelic richness of the Jamuna, Padma and the Halda population of catla were 4.800, 5.200, and 4.400, respectively. The average observed (Ho) and expected (He) heterozygosity values for the Jamuna, Padma and the Halda rivers were 0.720, 0.720 and 0.667 and 0.663, 0.678 and 0.643, respectively. The FIS values ranged from -0.341 to 0.121 and found to be nonsignificant while the pairwise FST values ranged from 0.0142 to 0.0507 and found to be significant. The genetic variations in the Jamuna and the Padma populations are comparable and slightly higher than that of the Halda population. Our study detected an excess of heterozygosity indicating recent genetic bottlenecks in the brood bank founder stocks of C. catla.
Key words: Microsatellite, population structure, bottleneck, assignment, family reconstruction.
The founder stock of a captive breeding program is prone to changes in genetic structure due to i... more The founder stock of a captive breeding program is prone to changes in genetic structure due to inbreeding and genetic drift. Genetic characterization of the founder population using suitable molecular markers may help monitor periodic changes in the genetic structure in future. To develop benchmark information about the genetic structure we analyzed six microsatellite loci in the Brodbank collections of rohu (Labeo rohita) originated from three major rivers—the Jamuna, the Padma and the Halda. A total of 28 alleles were detected in 90 individuals with an average of 4.6 alleles per locus. The average observed heterozygosity ranged from 0.655 to 0.705 and the expected heterozygosity ranged from 0.702 to 0.725. The mean FIS values were 0.103, 0.106 and 0.018 for the Jamuna, Padma and Halda fishes respectively. The population pair-wise FST values ranged from 0.0057 to 0.0278. Structure analysis grouped the fishes of the three rivers into two clusters. The numbers of half-sib families were 5, 5 and 4 and the numbers of full-sib families were 12, 10 and 18 for the Halda, Jamuna and the Padma samples respectively. Bottleneck was detected in all the river samples. We recommend to collect more fish from different locations of the major rivers to broaden the genetic variability of the founder stocks of the Brood bank. Keywords: Microsatellite, Genetic variation, Major carps, Brood bank, Bottleneck, Sib-ship