Genetic Variation within and among Iranian, French and Danish Rainbow Trout (Oncorhynchus mykiss) Using PCR-RFLP Analysis of Mitochondrial DNA Segments

The objective of this study was to investigate the genetic diversity within and between Iranian, French and Danish rainbow trout, Oncorhynchus mykiss. Mitochondrial DNA (mtDNA) of 135 samples (45per each breed), isolated by phenol-chloroform extraction method, was studied by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Fragments that included 986 bp of D-loop and 974 bp of Cyt b of mtDNA were amplified and investigated using different restriction enzymes. None of samples showed variation for restriction enzymes in D-loop. Using restriction enzymes, on gel electrophoresis, four different haplotypes were detected in Cyt b among which two breed specific haplotypes were observed in Danish population. AABBAB haplotypes had the most frequency with 61 events. UPGMA dendrogram based on cytochrome b gene showed that the Iranian population make cluster with French population rather than the Danish population. The genetic distance was 0.0008 between Iranian and French populations and 0.198 between both Iranian and Danish and French and Danish populations.