Genetic diversity of Mahisefid (Rutilus frisii kutum Kamensky 1901) in different rivers of the south Caspian Sea using PCR-RFLP




Mahisefid is the most popular fish in Iran with
the highest economic value. The analysis of mitochondrial DNA has been
extensively used as a marker for population genetic studies and is a powerful
tool in studies of gene flow and evolutionary biology. Two hundred ninety four samples
were collected from Sefid Rud River (100), Lamir River (98), Shir Rud River
(48) and Tajan River (48) during spawning season. Out of 24 enzymes tested,
four enzymes, namely TasI, HaeIII, HinfI and HincII were
selected for this study. In the present study,
the haplotype and nucleotide diversity of Mahisefid in four important rivers
where fingerlings are produced, were carried out by using PCR-RFLP at mtDNA
ND5/6 region. A total of 20 haplotypes were studied so that AAAA
and BAAA haplotypes had the most frequency. The average haplotype
frequency of AAAA and BAAA haplotypes were 29.93% and 27.55%, respectively. The
maximum nucleotide diversity was 0.94%, the minimum was 0.80% and the average
was 0.88%. Divergence between Lamir and Sefid Rud River and Shir Rud was 0.2%
and between Lamir and Tajan, and Shir Rud River it was 0.1%. The average
evolutionary distance was 0.015. The maximum evolutionary distance was 0.294
between ADAA and AAAB, ABAB and BDBA, BBAA and AABB. The average number of
bases surveyed was 121.2 and the average number of fragments was 30.30. The study suggests that there was a low genetic variability
in four populations of Mahisefid in the south of Caspian Sea. Mahisefid
population can be divided into two main clusters, the first clade
consists of Shir Rud River and Lamir River populations and the second clade
consists of Tajan River and Sefid Rud River populations. The clustering of
Mahisefid populations was not in accordance with
their geographical areas or river systems.