Phenotypic profiling based on body fluid traces discovered at the scene of crime: Raman spectroscopy of urine stains for race differentiation

• Published in: Analyst (London) Vol. 149; no. 2; pp. 581 - 59
• Main Authors: Vyas, Bhavik, Halámková, Lenka, Lednev, Igor K
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 07.10.2024
• Subjects: Adult; Body fluids; Crime; Criminal investigations; Differentiation; Female; Forensic Sciences - methods; Humans; Male; Middle Aged; Phenotype; Racial Groups; Raman spectra; Raman spectroscopy; Spectroscopic analysis; Spectrum analysis; Spectrum Analysis, Raman - methods; Urine
• ISSN: 0003-2654; 1364-5528; 1364-5528
• DOI: 10.1039/d4an00938j

Modern criminal investigations heavily rely on trace bodily fluid evidence as a rich source of DNA. DNA profiling of such evidence can result in the identification of an individual if a matching DNA profile is available. Alternatively, phenotypic profiling based on the analysis of body fluid traces can significantly narrow down the pool of suspects in a criminal investigation. Urine stain is a frequently encountered specimen at the scene of crime. Raman spectroscopy offers great potential as a universal confirmatory method for the identification of all main body fluids, including urine. In this proof-of-concept study, Raman spectroscopy combined with advanced statistics was used for race differentiation based on the analysis of urine stains. Specifically, a Random Forest (RF) model was built, which allowed for differentiating Caucasian (CA) and African American (AA) descent donors with 90% accuracy based on Raman spectra of dried urine samples. Raman spectra were collected from samples of 28 donors varying in age and sex. This novel technology offers great potential as a universal forensic tool for phenotypic profiling of a potential suspect immediately at the scene of a crime, providing invaluable information for a criminal investigation. Raman spectroscopy and machine learning were combined in this proof-of-concept study for the race identification of a urine stain donor with 90% accuracy. This method offers a powerful new tool for immediate suspect profiling at the crime scene.