Unlocking Identity: How Forensic DNA Testing is Bringing Closure to Nepal's Devastating Flood Victims

Police personnel in protective suits carry the body of an unidentified victim of the flash floods for storage at a crematorium in Kathmandu, Nepal [Dar Yasin/AP]. More than a week after a glacial collapse near the Langtang Lirung mountain peak set off devastating floods in Nepal and Tibet, sending a deluge of rocks, mud and water to the valleys below, forensic experts are working tirelessly to identify bodies.

Authorities reported on Thursday that more than 1,270 people have been killed, while over 4,700 remain missing. On Friday morning, reports emerged that two of the hundreds of workers trapped in tunnels at hydropower projects along the affected rivers had been successfully rescued. Meanwhile, authorities are utilizing DNA testing to identify hundreds of bodies that have left local morgues overflowing.

Police have urged first-degree relatives—including fathers, mothers, sons, and daughters—of the missing individuals to provide fresh blood samples for DNA profiling. For missing foreign nationals, a first-degree relative abroad can undergo DNA profiling in their home country and email the results directly to the Nepal Police for comparison. Hundreds of these DNA samples have already been collected and sent to the Nepal Police Forensic Science Laboratory and the Nepal Academy of Science and Technology.

Why is DNA testing needed?

In Nepal’s capital, Kathmandu, forensic teams are working diligently to identify recovered bodies, many of which have been found in a severely decomposed state, noted Al Jazeera’s Jessica Washington from a local DNA testing facility.

“Forensic teams on the ground told us that there are some things that can help with the identification process, such as tattoos and jewellery, but many bodies were found in such a state that it is very challenging to identify them,” Washington explained.

Experts note that decomposition is precisely why DNA testing has become essential. Mutilated bodies often turn unrecognisable, particularly after prolonged submersion in water. DNA profiles can be successfully generated from blood, soft tissue, bone, and teeth. Kerstin Montelius, a molecular biologist at Sweden’s National Board of Forensic Medicine, explained that DNA material can still be extracted from bone even when most of the soft tissue has decomposed.

“Visual identification might be impossible at an early stage of the process, with confusion as a result,” Montelius told Al Jazeera, while also cautioning that “DNA degrades, too, and circumstances set the decisions.”

How does DNA testing work?

The globally recognised framework for managing and identifying disaster victims is Interpol’s Disaster Victim Identification (DVI). DNA molecules contain the essential information that all living cells in the human body need to function. Apart from identical twins, who share nearly identical DNA, every person’s unique genetic makeup allows it to be effectively used for identifying disaster victims and missing persons.

As part of the DVI process, specialists inspect human remains to extract as much biometric data as possible. Montelius noted that DNA comparison, fingerprints, and teeth comparison are the three primary methods of identification that stand on their own with a high score of probability, with the chosen method depending entirely on the circumstances.

When a direct DNA profile of a missing person is available—such as a sample taken from personal items like a toothbrush or hairbrush—the unidentified body’s DNA is compared directly against it. However, when victims lack fingerprints or dental records, DNA profiles are collected from their next of kin via blood samples, as currently happening in Nepal.

Once collected, specialists compare and reconcile the two sets of data using various computer systems available on the market, which suggest potential matches for experts to scrutinize. Identification is formally declared upon achieving a 100 percent match between the datasets.

Are other countries helping?

According to the Indian embassy in Nepal’s capital, India has dispatched a 19-member forensic team that has begun analyzing DNA samples alongside their Nepali counterparts at the Nepal Police Central Forensic Science Laboratory and the National Forensic Science Laboratory. “The team is working to expedite the processing of DNA samples in Nepal for the identification of those affected by the recent flash floods,” stated the embassy.

Additionally, state-run Xinhua news agency reported on Thursday that China has sent a second contingent of DNA identification experts along with a third batch of emergency relief supplies.