Can lip prints provide biologic evidence?

BACKGROUND: Lip prints are unique and can be used in personal identification. Very few studies are available which establish them as biological evidence in the court of law. Thus, the objective of this study was to attempt to isolate DNA and obtain full short tandem repeat (STR) loci of the individual from the lip prints on different surfaces. MATERIALS AND METHODS: Twelve lip prints were procured on different surfaces such as tissue paper, cotton cloth, ceramic tile, and glass surface. Latent lip prints were developed using fingerprint black powder. Lipstick-coated lip prints were also collected on the same supporting items. DNA was isolated, quantified, and amplified using Identifiler™ kit to type 15 STR loci. RESULTS: Ample quantity of DNA was extracted from all the lip print impressions and 15 loci were successfully located in seven samples. Fourteen loci were successfully typed in 3 lip impressions while 13 loci were typed in 2 samples. CONCLUSION: This study emphasizes the relevance of lip prints at the scene of crime. Extraction of DNA followed by typing of STR loci establishes the lip prints as biological evidence too. Tissue papers, napkins, cups, and glasses may have imprints of the suspect's lips. Thus, the full genetic profile is extremely useful for the forensic team.