Optimization of DNA extraction protocol using skeletal remains found in Sri Lanka

Introduction

The preservation of DNA in old skeletal remains is reported to be very low in a tropical country like Sri Lanka due to prevailing climatic and environmental conditions such as high temperature, high rainfall and high humidity, etc. In this study, extraction of DNA from old skeletal remains dated back to 15 – 40 years was attempted by using previously published extraction protocols.

 

Materials and Methods

A 15-years-old humerus (15Y) excavated from Kuliyapitiya area in Kurunegala district and the 40-yearsold tibia (40Y) received from Department of Anatomy, Faculty of Medical Sciences, University of Sri Jayewardenepura were used to extract old DNA. Human mitochondrial HVS I region of extracted DNA was amplified in PCR using four overlapping first round primers and second round nested primers respectively. A second-round nested PCR was performed. PCR amplification success was verified upon electrophoresis in 2% agarose gels.

 

Results and Analysis

DNA bands were obtained with correct size ranges for all systems in both first and second round PCR products of amplified DNA extract of old bones 15Y and 40Y from modified phenolchloroform method. DNA bands were obtained from all four systems for 40Y bone DNA extract from DNA investigation Kit; QIAGEN, Germany.

 

Conclusion

In the present study, we have successfully extracted and amplified DNA from old skeletal remains by using modified phenol chloroform method and DNA investigation Kit – QIAGEN, Germany, nevertheless the preservation of DNA in skeletal remains in Sri Lanka is very low.