A straightforward technique to obtain genomic DNA from nasal swabs suitable for sheep SNP genotyping analysis

Abstract

Isolation of high quality and quantity genomic DNA is essential for molecular studies. It is crucial to select a non-invasive and straightforward technique to ensure the efficient collection of DNA, particularly at the farm level. The aim of this study was to determine if nasal swabs are an appropriate biological matrix to obtain good quality genomic DNA suitable for SNP genotyping. In this study, two biological matrices (blood and nasal swabs) were evaluated and compared for the isolation of genomic DNA obtained from 15 female Texel sheep. DNA quality and quantity were assessed using spectrophotometry and gel electrophoreses. Genotype concordance rates were used for comparison. Results showed that the highest concentration mean was obtained from blood samples (159.14 ng/µl), while from nasal swab samples the concentration mean was lower (130.12 ng/µl), but the difference was non-significant. Regarding purity, DNA obtained from nasal swabs presented a higher A260/A280 ratio (1.96), while the one obtained from blood samples was 1.90. Total DNA yield obtained from blood samples (15.91 µg) was significantly higher than the one obtained from nasal swabs (6.51). Blood and nasal swab genotyping concordance rates were high (mean = 0.984). In conclusion, our results indicate that nasal swabs can yield good quality DNA; however, the DNA extraction protocol should be optimized.