Detection of latent fingermarks and cells on paper

• Published in: Forensic science international Vol. 309; p. 110185
• Main Authors: Khuu, Alicia, Spindler, Xanthe, Roux, Claude
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier B.V 01-04-2020; Elsevier Limited
• Subjects: Benzaldehydes - chemistry; Deoxyribonucleic acid; Dermatoglyphics; DNA; DNA - chemistry; Fingermark; Fingerprint; Fingerprints; Forensic science; Forensic Sciences; Humans; Indanedione zinc; Indans - chemistry; Indicators and Reagents - chemistry; Investigations; Latent fingerprints; p-dimethylaminobenzaldehyde; Proof of Concept Study; Reagents; Recovery; Software; Thermal cycling; Touch DNA; Trace detection; Zinc; Australia; United States > US; p-dimethylaminobenzaldehyde; Trace detection; Fingerprint; Indanedione zinc; Fingermark; Touch DNA
• ISSN: 0379-0738; 1872-6283
• DOI: 10.1016/j.forsciint.2020.110185

•Fingermarks and cells detected following application of DMAB and IND-Zn reagent.•Different visualisation conditions allows for differentiation of the two traces.•Superior DNA profiling after use of combined reagent compared to IND-Zn alone.
Fingermarks and DNA are valuable traces in forensic investigations potentially allowing for the identification of the source of the trace or highlighting a link between a touched object and an individual. These traces are often latent and need to be detected before recovery. While a number of validated methods exist for fingermark detection, no routine method is in place for the detection of DNA. This study investigates the use of pdimethylaminobenzaldehyde (DMAB) in conjunction with indanedione zinc (IND-Zn) for the detection of latent cellular material and fingermarks on paper. The aim of this proof-of-concept study is to determine the successfulness of this reagent (DMAB-IND) in the detection of the respective traces and observe the impact it has on the resulting DNA profile. It was found that latent fingermarks and the associated cells could be visualised following treatment with the reagent. Samples treated with DMAB-IND showed a significantly higher percentage of alleles called compared to IND-Zn-treated and untreated samples due to the targeted recovery of cells. However, the reagent appears to degrade DNA at a rapid rate, requiring the treated samples to be processed for DNA on the day of treatment.