The extraction of sperm DNA from mixed stain using DNase-Ⅰ purification combined with alkaline lysis method / 中国法医学杂志

Objective To establish a method of sperm DNA extraction in mixed stain by using DNase-Ⅰ purificationcombined with alkaline lysis method in forensic science.Methods 79 mixed stain samples of criminal cases were collected.Sperm DNA was extracted using the purification of DNase-Ⅰ binding alkaline lysis method.16 STR loci were genotyped with fluorescent multiplex amplification system.The typing results were compared with that of extracted using two-step differential extraction procedure.Results Of all 79 mixed stain samples,64 samples were genotyped successfully by using DNase-Ⅰ purification combined with alkaline lysis method while 57 samples were genotyped successfully with two-step differential extraction procedure.There was significant difference between two methods(P=0.039).The purification of DNase-Ⅰ binding alkaline lysis method had a higher success rate and lower cost than that of two-step differential extraction procedure.Conclusion Purification of DNase-Ⅰ binding alkaline lysis method can increase the typing success rate of the mixed stain samples.The method is simple,rapid and easy to be automated,and suitable for forensic identification test.

IDENTIFICATION OF VAGINAL SECRETION STAINS AND MIXED STAINS ACCORDING TO THE SDS-PAGGE BAND PATTERN OF VAGINAL FLUID / 中国法医学杂志

This paper reports the identification of vaginal secretions from the following stains by SDS-PAGGE,i.e.vaginal secretion stains and mixed stains kept at—30℃,4℃ for 3 years and at roomtemperature for 9 years.The method was applied to the forensic practice.

PREPARATION AND PURIFICATION OF ANTI HUMAN SEMINAL PECULIAR PROTEIN / 中国法医学杂志

This paper is reports the preparation and purification of anti-human seminalpeculiar protein (AS-PP) serum for the purpose of determining ABO blood groupin seminal stains mixed with vaginal secretions.