Tissue boiling: a short-cut in DNA extraction for large-scale population screenings

• Published in: Molecular ecology 1998-09, Vol.7 (9), p.1243-1245
• Main Author: VALSECCHI, E.
• Format: Article
• Language: English
• Subjects: Animals; Anura - genetics; Brackish; DNA, Mitochondrial - chemistry; DNA, Mitochondrial - isolation & purification; Female; Fishes - genetics; Freshwater; Hot Temperature; Lizards - genetics; Male; Marine; Megaptera novaeangliae; Mollusca; Platypus - genetics; Polymerase Chain Reaction - veterinary; Population Dynamics; Sequence Analysis, DNA; Skin - chemistry; Snails - genetics; Whales - genetics
• ISSN: 0962-1083; 1365-294X
• DOI: 10.1046/j.1365-294x.1998.00379.x

While genetic methodologies are becoming more and more popular in zoological studies, their application usually requires long processing times. This paper presents an effective way to quicken molecular typing by reducing DNA-extraction time to 15 min. The short cut was achieved simply by boiling the tissue samples in a buffer solution, in the absence of chelating agents, silica particles and proteinase K. This procedure allows DNA molecules to be released into the boiling solution which can be directly used as PCR template for both nuclear and mitochondrial genetic analyses. Although similar procedures have been explored in medical diagnostic science (e.g. Sepp et al. 1994; Afghani & Stutman 1996), little importance has been given to the application of boiling-DNA-extraction techniques in ecological studies. This is probably due to zoological DNA samples commonly needing to be typed for different molecular markers, often at different stages of the research. Consequently, DNA-extraction products need to be long-lasting, a characteristic which has not been extensively tested in previously described boiling methods. The proposed methodology, which was successfully tested on a range of tissues from most diverse taxa, yields DNA templates which can be analysed even 3 years after being extracted. Most samples tested in this study were collected from cetaceans (303). Howevaer, additional samples, representing five classes of Vertebrates and one phylum of Invertebrates (Mollusca), were also included (Table 1). Most tissue samples were pieces of sloughed skin collected from free-ranging humpback whales (Megaptera novaeangliae) in the course of an extensive population study (Valsecchi 1997). For the remaining species, biological samples were available from skin, muscle, liver or from body structures, such as tails, toes and feathers.