Assessment of The Influence of Temperature on Brain DNA Quality for Forensic Studies Using RAPD Marker

Abstract

Forensic samples may need to be preserved for an extended period, therefore determining an optimal temperature that allows for quality DNA to be obtained when required is essential. This study seeks to ascertain the influence of temperature and postmortem time on the quality of brain DNA for forensic studies. Seven (7) albino Sprague-Dawley mice weighing between 20 – 30 grams were used for this study. One (1) mouse which served as the control was sacrificed and the brain tissue harvested for DNA extraction immediately. The remaining six (6) were divided into two groups, where one group's harvested brain tissues were stored at room temperature of 24^°C and the other group's harvested brain tissues were preserved by freezing at -18^°C. DNA was extracted from the brain tissues of one mouse each from the two groups after they had been stored at the different temperatures for 24, 48 and 72 hours. DNA extraction was done using DNA extraction kit from APS Life Tech West Africa Limited and PCR was carried out on each of the DNA extracts using RAPD-OPC-04 primer. DNA concentration and # extracted DNA was determined by spectrophotometry analysis, and the gel electrophoresis was also done to determine the DNA band quality. The results the best nuclear DNA quality is obtained from freshly harvested brain tissues, the quality of nuclear DNA from brain tissue is better preserved by freezing the brain tissue for long periods than at room temperature.