Abstract: Objective To probe the feasibility of PCR-STR typing of hair root without sheath cells with current and redesigned miniSTR amplicon primers. Methods The DNA of the hair root without sheath cells is amplified by both current and miniSTR amplicon primers and checked by PAGE. Results The correct typing of hair root without sheath cells with MiniSTR amlicon primers and current primers is respectively: D8S1179 11.4%&17.1%;D21S11 3.7%&5.9%; vWA 22.2%&33.3%;THO1 9.3%&5.6%;D16S539 0&9.2%.The ladder-like bands detected in the PCR-STR typing of hair root without sheath cells is strongly disturb the result. Conclusion The DNA typing of hair root without sheath cells can be resolved limitedly with the two primers and Ladders-like bands should also be paid attention to in forensic casework.

Key words: short tandem repeats, hair root without sheath cells, PCR-STR profiling, miniSTR primers, established primers, ladder-like bands