Buccal swabs for long-term DNA storage in conservation genetics of fish: One-and-a-half-year analysis timeframe

Conservation genetic research is essential for the management and recovery of endangered taxa. However, the invasive collection of biological material for DNA analysis is controversial. From an ethical perspective, non-destructive sampling methods leave the aquatic specimen alive and less invasive procedures minimize stress on the animals. DNA can be obtained from fish using minimally invasive techniques such as buccal swabs. Here we evaluated the performance of buccal swabs for long-term storage of DNA obtained from brown trout (Salmo trutta). The buccal swabs were stored at room temperature and cut into pieces, one part of which was used for extraction of an aliquot and the others were stored as a “biobank” of biological material. The elapsed time from sampling to molecular analysis was one and half year. The amplification of three different DNA targets was tested to assess the effectiveness of the extraction: mitochondrial DNA (the D-LOOP region), nuclear DNA (the LDH gene) and microsatellite DNA at multiple loci. The results showed high quantification (mean value: 281.84±72.4 ng/μL), indicating that DNA could be effectively extracted from the buccal swabs. Our study results suggest that buccal swabs for long-term storage of DNA at room temperature are promising for use in field conservation studies.