A bone sample cleaning method using trypsin for the isolation of DNA

Cleaning the surface of bone samples is a necessary step to remove contaminants prior to isolating DNA for forensic DNA analysis. In this study, a simple trypsin method for cleaning bone samples prior to DNA isolation was developed. Cleaning the surface of human bone samples was achieved by the application of trypsin solution. Light microscopy and scanning electron microscopy results indicated that trypsin treatment was effective in removing the outer surface of bone samples. The yield of DNA isolated from trypsin-treated bone samples was sufficient for subsequent short tandem repeat (STR) analysis. STR analysis revealed no adverse effect on the DNA profile after the trypsin treatment. The data suggest that this trypsin method can potentially be an alternative cleaning method to mechanical cleaning methods.