Preparation of mitochondrial DNA from long-term preserved and accident carcass organs in animals

Abstract

Physical effects of sampling conditions and preservation time on the nature of mitochondrial DNA (mtDNA) were studied by analyzing electrophoretic patterns and measuring volume and purity of mtDNA which was fractionated and extracted from organs preserved for a maximum 1.4 years in eight animal species. The analysis showed that the volume and purity of the prepared samples did not differ significantly between long-term preserved and fresh organs. Also, no physical effect of the long-term freezing preservation on the cleavage patterns was detected in the results using eight restriction endonucleases. Non-degenerate mtDNA was extracted from the livers of Japanese Sika deer which died in accidents, and the organs preserved at less than -80°C for one year. Almost no physical effect on volume or purity of the prepared mtDNA was observed. When mitochondria was fractionated from organs of animals without bleeding and with fatty livers, the non-degenerate mtDNA was obtained more by repeated washings with the homo buffer and careful cutting with scissors. From the above results, even if organs are obtained under inferior sampling conditions, as in the case of wild animals which died by traffic accidents, mtDNA obtained by fractionation can be used to study cytoplasmic inheritance. It is suggested that accident carcasses of wild animals, which are also important as gene resources can be efficiently used for academic researches.