Monday, November 30, 2020

Fingerprints Yield Sex Info

Must read

FBI Validates STRmix™ for Use on Up to Five-Person Mixtures

The Federal Bureau of Investigation (FBI) has published its validation of STRmix™ for use on mixtures of up to five persons, as well as...

Technology Recreates What Jesus May Have Looked Like at Age 12

Using the same technology that adds wrinkles to the drawings of Mafia bosses to identify them after decades on the run, the Italian police...

Has forensic science made it impossible to commit the perfect crime?

Has forensic science made it impossible to commit the perfect crime? Sarah Freeman meets a leading professor who always tries to be one step...

How to Find Bloodstains

The Smithsonian Channel series: Catching Killers have created an informative video to show when criminals clean up after a violent crime, bloodstain pattern analysts use luminol, one of...
Michael Whyte
Crime Scene Officer and Fingerprint Expert with over 12 years experience in Crime Scene Investigation and Latent Print Analysis. The opinions or assertions contained on this site are the private views of the author and are not to be construed as those of any professional organisation or policing body.
- Forensic Podcast -

To identify a person from their fingerprint, computers traditionally require a clean image of the patterns in the skin and a pre-recorded fingerprint sample to match it to. But a research group led by Jan Halámek from the University at Albany, State University of New York, has taken fingerprint identification to a new level by removing the amino acids from a fingerprint and using them to determine whether the culprit was male or female. The results were published last month (October 13) in Analytical Chemistry.

Males and females leave different levels and compositions of amino acids in their fingerprints. Previous studies had used the amino acid composition in fingerprints to differentiate between the two, but relied on instruments such as mass spectrometers. Halámek and his team devised a simpler method.

The team had volunteers—three males and three females—press their fingertips against a polyethylene surface. To extract amino acids from the leftover prints, which are mostly oil, lipids, and sweat, the researchers then added an acidic solution and heated up the polyethylene; this caused the amino acids to migrate into the solution.

When they used a bioassay to test the resulting compounds, the team was successfully able to distinguish between the male and female subjects. Among other differences, females leave higher levels of amino acids in their fingerprints overall. The female subjects also left fingerprints on a door knob, a laminate desktop, a composite benchtop, and a computer screen, and the researchers were able to extract the amino acids from these surfaces.

The method seemed simple and cheap, Stephen Morgan, a chemist at the University of South Carolina, told Chemical & Engineering News—a benefit compared to other options. Halámek has since transferred the reaction components onto paper to make a quick, easy-to-read test similar to pregnancy strips or glucometers, which can be used and understood by people without scientific backgrounds, he told Chemical & Engineering News.

Source: The Scientist

- Advertisement -

More articles

- Advertisement -

Latest article

Trees and shrubs might reveal the location of decomposing bodies

Plants could help investigators find dead bodies. Botanists believe the sudden flush of nutrients into the soil from decomposition may affect nearby foliage. If...

Are Detectives discounting the associative value of fingerprints that fall short of an identification in their investigations?

Every day, Fingerprint Experts in every latent office across the globe examine fingermarks that they determine to fall short of an identification....

Using the NCIC Bayesian Network to improve your AFIS searches

This National Crime Information Centre (NCIC) Bayesian network is based on the statistical data of general patterns of fingerprints on the hands...

DNA decontamination of fingerprint brushes

Using fingerprint brushes across multiple crime scenes yields a high risk of DNA cross-contamination. Thankfully an Australian study has discovered a quick and easy way to safely decontaminate fingerprint brushes to prevent this contamination risk and allows the brushes to be safely reused even after multiple cleaning cycles.

Detection of latent fingerprint hidden beneath adhesive tape by optical coherence tomography

Adhesive tape is a common item which can be encountered in criminal cases involving rape, murder, kidnapping and explosives. It is often the case...