Extraction of DNA from plastinated tissues

Abstract

Introduction: Plastination allows anatomical samples to be preserved in excellent condition for an indefinite period, free of formalin, and in a format that allows biosafe manipulation by students, academics, and researchers. As with other tissue preservation techniques, it is important to establish the level of conservation of deoxyribonucleic acid (DNA) for use in future applications. The object of the present work was to extract and evaluate DNA from plastinated tissues.

Methods: We used samples of liver from Canis lupus familiaris and skeletal muscle from Rattus norvegicus, Sprague-Dawley strain, extracted from specimens plastinated with silicone at room temperature. The tissue samples were deplastinated by incubation in 5% sodium methoxide dissolved in methanol for 24 or 48 h. The samples were divided into two equal parts and DNA was extracted using two different protocols. After extraction, the DNA was quantified by fluorometry and its integrity was assessed by electrophoresis in a 1% agarose gel.

Results and discussion: A high yield of DNA was obtained from the deplastinated samples and the DNA was intact. Plastinated tissues have proven to be stable and easily managed. They can also be used for examination under light and electron microscopes. The DNA extraction technique used here allowed us to obtain intact DNA from samples plastinated with silicone at room temperature, without previous fixing. This technique may allow tissue specimens to be preserved for retrospective studies of archived samples of normal and pathological anatomy in the fields of basic, clinical, forensic, and epidemiological sciences.

Conclusions: The extracted DNA was intact and suitable for use in subsequent applications. Obtaining whole DNA from plastinated samples using tissue preservation protocols that preserve the tissue for use in subsequent applications, like real-time PCR, opens up many possibilities, with applications in the basic and clinical sciences, epidemiology, and forensic science.

Keywords: DNA extraction; Deplastination; Plastination; Real-time PCR.