LAUSR

Abstract Dandruff is generally presented in criminal cases, and it contains some nucleated cells which make it possible to extract DNA for forensic uses. EZ-tape, an extraction tool for exfoliative cells, developed by Institute of Forensic Science, Ministry of Public Security, is widely used in China. Dandruff was collected by EZ-tape together with other indefinite particles, and DNA was extracted directly from EZ-tapes. In this study, we aimed to improve the utilization of samples by isolating single pieces of dandruff from 3M scotch tapes for subsequent DNA profiling. We compared the DNA profile results of single pieces of dandruff and EZ-tape. In addition, we tried to explore whether the oscillation can affect the alleles recover. Results indicated that 56% of single pieces of dandruff with oscillation obtained full STR profiles compared with 11% with non-oscillation. Single pieces of dandruff could provide enough DNA for STR genotyping and rare sample (12.5%) could be identified mixture. Besides, both contributors are detected. However, 41.7% of samples collected through EZ-tape missed one contributor and 33.3% were mixture. Therefore, dealing with single piece of dandruff may be a potential alternative for individual identification in some special forensic casework.