Majeed Sh. S. Al-Omairi (1)
General Background Genetic diversity is essential for ensuring species resilience and supporting long-term ecological stability. Specific Background Silurus glanis, an ecologically and economically important freshwater fish in Iraq, is increasingly exposed to environmental pressures that may shape its genetic composition. Knowledge Gap Yet, information on the genetic variation between populations inhabiting the Euphrates and Tigris Rivers remains limited, particularly when assessed using RAPD-PCR molecular markers. Aims This study aims to evaluate the genetic diversity of S. glanis from both rivers using five RAPD primers to identify patterns of genetic similarity and differentiation. Results Analysis of 120 samples revealed 13 genetic loci, with 83.842% similarity and 16.154% genetic variation, indicating low diversity but high interpopulation resemblance. Novelty The study provides an updated genetic profile demonstrating the influence of local environmental conditions on the species’ genetic structure and suggesting potential gene flow between riverine populations. Implications These findings highlight the need for strengthened river ecosystem management and the application of molecular biomarkers to guide conservation strategies capable of preventing further genetic erosion and supporting the long-term sustainability of S. glanis populations.Highlight :
The results show measurable genetic variation and high similarity between the two river populations.
RAPD-PCR markers detected differences across loci that reflect environmental influences on genetic structure.
The findings highlight the importance of monitoring river conditions to maintain the species’ genetic stability.
Keywords : Genetic diversity, RAPD-PCR, Silurus glanis, Euphrates and Tigris populations, molecular markers
F. A. Atienzar, A. Cordi, B. Donkin, C. Evenden, A. M. Jha, and J. K. Chipman, “Evaluation of the RAPD Assay for the Detection of DNA Damage and Mutations,” Mutation Research, vol. 521, no. 1–2, pp. 151–163, 2002, doi: 10.1016/S1383-5718(02)00230-9
A. D’Agostino, S. Rossi, L. Marino, and F. Casu, “Genetic Diversity in Fish Populations: Application of RAPD-PCR in Different Aquatic Environments,” Journal of Fish Biology, vol. 98, no. 4, pp. 1067–1081, 2021, doi: 10.1111/jfb.14606
S. De Flora, C. Camoirano, and P. Bagnasco, “Multiple Genotoxicity Biomarkers in Fish Exposed In Situ to Polluted River Water,” Mutation Research, vol. 319, pp. 167–177, 1993, doi: 10.1016/0165-1218(93)90058-G
M. Gholami, A. N. Taghizadeh, and R. Ghasemi, “Molecular Markers for Assessing Genetic Variation in Fish Populations: A Review of RAPD-PCR Studies,” Aquaculture Research, vol. 51, no. 7, pp. 2840–2852, 2020, doi: 10.1111/are.14616
A. Kumar, A. Sharma, and R. Mishra, “Use of RAPD-PCR for the Assessment of Genetic Diversity in Different Mushroom Species,” Current Science, vol. 86, no. 10, pp. 1367–1371, 2004
L. Rocco, R. Peluso, L. Stingo, and L. Costagliola, “Genotoxicity in Zebrafish (Danio rerio) Exposed to Two Pharmacological Products From an Impacted Italian River,” Journal of Environmental and Analytical Toxicology, vol. 1, p. 103, 2012, doi: 10.4172/2161-0525.1000103
R. Shah, Z. Khan, M. Ali, and T. Rahman, “Genetic Diversity and Population Structure of Fish Species Using RAPD-PCR Technique,” Molecular Genetics and Genomics, vol. 294, no. 3, pp. 657–670, 2019, doi: 10.1007/s00438-018-1524-3
S. Sharma, V. Taneja, and P. Kaur, “Genetic Diversity of Escherichia coli Isolates From Different Sources Using RAPD-PCR Analysis,” Indian Journal of Medical Microbiology, vol. 24, no. 3, pp. 178–182, 2006, doi: 10.4103/0255-0857.27191
J. Welsh and M. McClelland, “Fingerprinting Genomes Using PCR With Arbitrary Primers,” Nucleic Acids Research, vol. 18, pp. 7213–7218, 1990, doi: 10.1093/nar/18.24.7213
J. G. K. Williams, A. R. Kubelik, K. J. Livak, J. A. Rafalski, and S. V. Tingey, “DNA Polymorphisms Amplified by Arbitrary Primers Are Useful as Genetic Markers,” Nucleic Acids Research, vol. 18, pp. 6531–6535, 1990, doi: 10.1093/nar/18.22.6531
F. C. Yeh and R. Yang, POPGENE: Microsoft Windows-Based Freeware for Population Genetic Analysis, University of Alberta, Edmonton, Canada, 1999
P. Bardakci, “Random Amplified Polymorphic DNA (RAPD) Markers,” Turkish Journal of Biology, vol. 25, no. 2, pp. 185–196, 2001
E. R. Rocha-Olivares and B. R. Vetter, “Effects of Sample Size, Molecular Marker Choice, and Population Subdivision on the Estimation of Genetic Diversity in Marine Fishes,” Canadian Journal of Fisheries and Aquatic Sciences, vol. 56, pp. 1938–1946, 1999, doi: 10.1139/f99-128
K. A. Naish and D. R. Hard, “Bridging the Gap Between the Genotype and the Phenotype in Fish Populations,” Fish and Fisheries, vol. 9, no. 4, pp. 396–422, 2008, doi: 10.1111/j.1467-2979.2008.00302.x
C. Liu, X. Sun, and Y. Li, “Application of RAPD and Microsatellite Markers for Genetic Analysis in Aquatic Organisms,” Aquaculture International, vol. 17, no. 3, pp. 219–232, 2009, doi: 10.1007/s10499-008-9193-y