Possibilities of DNA Identification of Foreign Sweat and Grease Substance on Human Skin

Abstract

Contact traces on a human body are a widespread object investigated in cases involving criminal acts against a person. In such cases, interpretation of the results of DNA analysis, as the most evident method, is accompanied by considerable difficulties. This paper shows the possibility of detecting genetic material in the sweat and grease deposits left by the donor on the skin surface of a living recipient. The comparative study of DNA amount in the sweat and grease substance on the surface of the skin of different areas of the body of men and women is carried out. Typing of microsatellite loci of autosomal DNA and Y chromosome in swabs from places of contact of donor males with integuments of recipients of both sexes is carried out. No statistically significant differences in the DNA amount of sweat and grease substance depending on its localization on human body are revealed. The DNA study of sweat and grease substance left by donor men on the skin of both men and women in half of cases reveals allelic combinations inherent in both the donor and the recipient. The results obtained indicate equal chances of detecting the DNA of contacting individuals.