Assessment of Genetic Diversity, Gene Flow and Demographic History of Frigate Tuna (Auxis thazard) Populations in Tanzanian Marine Waters Using Mitochondrial DNA Control Region

Aim: To investigate genetic diversity, gene flow and demographic history of frigate tuna (Auxis thazard) populations found in Tanzanian marine waters.
 Study Design: The study used a descriptive research design whereby fish samples were randomly collected from four locations the variation within among analyzed using mitochondrial DNA (mtDNA) control region.
 Place Duration Study: Fish landing sites Tanga, Dar es Salaam, Mtwara Zanzibar, Tanzania. was conducted between July 2020 June 2021.
 Methodology: A total 100 sampled small-scale fishermen at Dar-es-Salaam (20), Tanga (30), Zanzibar (20). For each fish, 50 g muscle tissue obtained put vial containing 95% ethanol. extracted commercial Kit (Quick-DNATM Miniprep Plus Kit, Zymo Research Corp.) according to instructions manufacturer fragment 432 bp mtDNA region amplified sequenced ABI PRISIM™ 3100 Genetic Analyzer (Applied Biosystems). Haplotype nucleotide historic estimated 92 samples.
 Results: 88 haplotypes identified all samples. highest haplotype diversity (1.000 ± 0.017) 0.010) while lowest observed population (0.992 0.012). had (0.078 0.018) Salaam (0.016 0.009). differentiation (FST) (0.178) (0.016). distances pairs small. phylogenetic tree revealed two main clusters. Cluster 1 which consisted nine dominated by with seven remaining reference sequences Euthynnus affinis (Kawakawa tuna). II 84 individuals populations, no specific subcluster. number immigrants per generation (Nm=18.310) (Nm=1.180). neutrality test indicated negative values, suggesting recent expansion.
 Conclusion: There is high but there significant that comprise single panmictic population.