The Role of Lipsticks and Blush Sticks in Genetic Profiling for Human Identification

The core objectives of the current study are to generate human DNA profiles from used lipsticks and blush sticks of various brands available in Pakistan. A total of 12 international and local brands of lipsticks and blush sticks were selected. The lipsticks and blush sticks were applied by twenty different healthy female volunteers of 21-30 years of age. The heads of used lipsticks and blush sticks were swabbed with dry sterile cotton swabs. The qualitative and quantitative analysis was done by real time polymerase chain reaction (PCR), using a Quantifiler® Duo DNA Quantification Kit on Real Time PCR ABI™ 7500. Samples were amplified for 16 STR loci using an AmpFlSTR® Identifiler® PCR amplification kit on Thermocycler ABI 9700. The amplified product was run on Applied Biosystems 3130™ Genetic Analyzer. The genetic profiles were analyzed on GeneMapper® ID-X software version 1.0. The quantification results showed that the yield of DNA obtained from lipstick samples was greater than that of DNA obtained from blush stick samples. The real-time PCR results showed that only 16% of cosmetic samples had shown inhibition. The DNA profiles obtained from all blush stick samples were of good quality compared to those from lipstick samples. No profile was obtained from one blush stick sample (DNA 0.001 ng/μL) and four lipstick samples (DNA 0.001-0.003 ng/μL) because the amount of DNA in each of these samples was less than the amount required for successful amplification. DNA profiles were successfully generated from most of the samples of various available brands of lipsticks and blush sticks. This is the first study proving that DNA profiles can be generated from various lip and face cosmetics.