Temporal Variation of Genetic Diversity in Rutilus rutilus Populations from Lithuania Using mtDNA Markers in the Context of Anthropogenic Activities.

One of the most abundant fish species, Rutilus rutilus, is widely distributed in Lithuania and its potential to adapt to environmental changes attracted our interest. Unfortunately, it is not properly understood how anthropogenic activities can affect the genetic diversity within this species. We studied three populations of roaches (samples collected in the Neris and Žeimena rivers, and Lake Drūkšiai) over a period of five years (from 2017 to 2022) to determine genetic diversity using mtDNA D-loop and ATP6 genetic markers. Genetic diversity parameters, AMOVA analysis, haplotype network, and PCoA analysis revealed a greater genetic variability in roach samples collected in 2017, and the greatest differences were noticed in the population inhabiting Lake Drūkšiai, as compared with other samples studied over a five-year period. Differences in genetic diversity detected after a five-year period led us to the assumption that roach populations may be related to the effects of natural (changing climatic conditions) and anthropogenic (operating nuclear power plant) origin. [ABSTRACT FROM AUTHOR]