The use of DNA profiling in identifying murderers and sexual abusers : a case report

الملخص EN

A complaint was registered at a Police Station in the Faisalabad District of Pakistan.

A boy aged 7-8 years went to a nearby shop and never came back.

He was last seen with the accused by eyewitnesses.

The naked dead body of the boy was found tied with his clothing in nearby fields.

An autopsy revealed three incised wounds on the neck.

Evidence material from the dead body and crime scene were submitted for forensic analysis.

The evidence material was screened for human biological fluids, semen, and blood.

The items positive for semen or blood were subjected to DNA extraction.

Short Tandem Repeat (STR) markers were amplified from extracted DNA after quantification.

The amplicons were subjected to capillary electrophoresis to generate DNA profiles.

Mixture DNA profiles were interpreted by EuroForMix, the probabilistic genotyping software.

Post-mortem examination indicated the possibility of sexual abuse of the boy prior to his killing.

Seminal material was found on anal swabs collected from the dead body.

The DNA profile obtained from anal swabs was consistent with a mixture of the DNA profiles of both the suspect and the victim.

The DNA profile of the suspect was also found in nail swabs taken from the victim.

The DNA profile generated from blood stains present on the suspect’s clothing matched the DNA profile of the victim.

The DNA of the suspect was present on anal and nail swabs collected from the victim.

The victim’s DNA was present in blood stains present on the suspect’s clothing.

The suspect was confirmed to be the perpetrator.