More than just bites: Bedbugs can retain human DNA for up to 45 days | WPN World People News

A research team in Malaysia has recently revealed that bedbugs—those blood-sucking pests that make people’s skin crawl—may have unexpected value in criminal investigations. Scientists have confirmed that after feeding on human blood, bedbugs can retain human DNA in their bodies for up to 45 days, making them a potential source of biological evidence at crime scenes.

The Science University of Malaysia (USM) in Penang has long studied the tropical bedbug Cimex hemipterus and published its findings in the international journals Scientific Reports and Forensic Science International. Beginning in 2014, the researchers collected samples and demonstrated that even more than a month after feeding, human genetic information—such as characteristics related to eye, hair, and skin color—could still be extracted from the insects.

According to lead researcher Abdul Hafiz Ab Majid, the team used forensic techniques such as short tandem repeats (STR) and single nucleotide polymorphism (SNP) analysis. They were able to reconstruct DNA profiles immediately after the insects fed, and even after 45 days, partial genetic data could still be recovered. He emphasized that if bedbugs are collected at a crime scene, they may contain DNA from individuals who were present, offering new investigative possibilities when traditional evidence like bloodstains or fingerprints is absent.

Compared with commonly studied mosquitoes, bedbugs have a far more limited range of movement and tend to remain hidden in mattresses, crevices, and pillow seams. Because their bodies swell significantly after feeding, they are unable to move far from the location, increasing the likelihood that they retain the DNA of the person they bit. Researchers noted that bedbugs have long been overlooked as forensic subjects, and they hope their work will fill this gap in the field.

Although this technique has not yet been formally adopted by the justice system, local public safety experts believe bedbugs could become a supplementary tool in future forensic science. In complex cases or in situations where a crime scene has been cleaned, these “tiny creatures hiding in furniture” may offer crucial clues. While the duration of DNA preservation is still limited and only basic physical traits can currently be identified, the scientific community remains highly optimistic about potential future applications.