Rapid Isolation of DNA from the Mucus of Asian Arowana (Scleropages formosus, Osteoglossidae)

Abstract

Owing to arowana being listed in CITES, DNA diagnostics should not rely on conventional methods of obtaining tissue samples. A non-invasive method of obtaining material containing DNA has been developed. Mucus samples for DNA isolation can be obtained by cotton swabbing the arowana body surface with subsequent purification of DNA
fragments by using phenol/chloroform. DNA sample quality is assessed by UV absorbancy at wave lengths of 260 nm and 280 nm, as well as by calculating the absorbancy ratio involving 260 nm/280 nm results in order to determine DNA sample quality and quantity. Electrophoresis is employed to assess DNA quantity and quality (DNA molecular weight
compared to standard DNA, RNA contaminant, DNA double strand breakage, and protein or phenol contaminants). The DNA isolated from mucus is of good quality with little RNA contamination. Although statistics (hypothesis test) suggest that the DNA quantity of samples taken from gills and mucus is significantly different at the 95% significance level, the
amount of DNA contained in mucus is sufficient for analysis.