ABSTRACT
Studies on genetic diversity require biological material containing a reliable source of DNA that can be extracted and analyzed. Recently, non-invasive sampling has become a preferred sampling method of biological material. The suitability of a less invasive approach that involves obtaining samples by swabbing the fish skin (including live, non-anesthetized fish) should be considered. In this study, we compared the efficiency of DNA extraction, amplification, and sequencing of mtDNA fragments of two fish species Perca fluviatilis and Rutilus rutilus based on DNA collected from the scales and mucus using the modified Aljanabi and Martinez method. The results revealed a higher quality of DNA extracted from the mucus; however, the mean DNA concentration obtained from the scales of both fish species was higher. We verified the method suitable for amplification and sequencing of mtDNA fragments of both fish species using newly designed markers (D-loop, ATP6) and examined the potential risk of intraspecific cross-contamination. The DNA sequence alignment analysis revealed identical sequences attributed to the same individual when DNA, extracted from two different sources (scales and mucus), was used. We demonstrated that the quantity and quality of DNA extracted from the scales and mucus using the proposed method were high enough to carry out genetic diversity studies based on sampling of live fish with the possibility to release it after collecting samples.
ABSTRACT
The intraspecific genetic diversity of freshwater fish inhabiting hydro-systems of the macrogeographic area spreading from the Black to Baltic Seas requires comprehensive investigation from fundamental and practical perspectives. The current study focused on the involvement of the mtDNA ATP6 region in the adaptability and microevolution of Perca fluviatilis within phylogeographic and anthropogenic contexts. We sequenced a 627 bp fragment encompassing the ATP6 region and used it for genetic analysis of 193 perch caught in Latvia, Lithuania, Belarus, and Ukraine, representing natural and anthropogenically impacted populations. We evaluated patterns of intraspecific genetic diversity in the ATP6 region and phylogeographic trends within the studied area compared with previously established D-loop trends. Evaluation of ATP6 coding sequence variability revealed that among 13 newly detected haplotypes, only two were caused by non-synonymous substitutions of amino acids of the protein. PCoA revealed three genetic groups (I-III) based on the ATP6 region that encompassed four previously described genetic groups established based on the mtDNA D-loop. The two mtDNA regions (D-loop and ATP6) have microevolved at least partially independently. Prolonged anthropogenic impacts may generate new point mutations at the ATP6 locus, but this phenomenon could be mainly concealed by natural selection and reparation processes.
ABSTRACT
The European Turtle Dove, Streptopelia turtur, a long-distance migrant wintering in Africa, is a widespread Palearctic species. This species is classified as vulnerable and is undergoing a long-term demographic decline. The results of the previous study (based on mitochondrial (mtDNA) cytochrome-b (cytb) sequences of birds from Western and Southern Europe) indicated that the species was not genetically structured. We analysed the mtDNA cytb and D-loop of 258 birds collected from Morocco, Spain, and Ukraine. High genetic variability, expressed by haplotype diversity and nucleotide diversity, was revealed in both cytb (Hd = 0.905 ± 0.009, π = 0.00628 ± 0.00014) and the D-loop (Hd = 0.937 ± 0.009, π = 0.01502 ± 0.00034). SAMOVA and principal coordinates analysis revealed the birds belonged to two genetically distinct groups. One group included birds collected in Spain, while birds sampled in Morocco and Ukraine formed another group. Furthermore, significant genetic differentiation was identified between Turtle Doves from Morocco and Ukraine, and certain Spanish samples. The present results indicate that specific management and conservation plans relevant for the species in various regions should be applied. However, further nuclear DNA research and new studies (particularly in Eastern Europe) are necessary for the decisive results on genetic structure of this species.
