Sometimes it takes weeks or even years — Forensic pathologist and DNA expert on identification process

Getting DNA results for 62 people who were burned beyond recognition when a fire broke out in a building in Marshalltown, Johannesburg might not be an easy or quick journey for their relatives. 

Initially the department of health reported 10 bodies of the 76 people who died last Thursday were burnt beyond recognition. This number, however, increased to 62 by Friday morning after the bodies were examined by forensic pathologists.

TimesLIVE spoke to the South African Academy of Forensic Sciences chairperson, Dr Stefan Jansen van Vuuren, about how the DNA identification process generally works. 

Jansen van Vuuren, who works as a forensic pathologist in Free State, said it was hard to estimate how long results for the 62 bodies would take as this could be affected by factors including resources.   

“Generally it should take days to get DNA results but from a practical point of view, it does take longer.

“We [forensics pathologists] wait a long time for DNA results, depending on the laboratory and where the samples come from. In my experience it can take anything from two to nine years,” he said.

The forensic pathologist said this might not be the case in the mass casualty disaster should a forensics disaster unit be set up in Gauteng to fast-track results. He said in some cases where pressure was expedited the results came out within weeks.

“Each province has its own forensic pathology services. According to their mass disaster plan they would have to allocate resources to sort out the death investigations (postmortems) and identification process.”

Police laboratories which process DNA samples sometimes experience backlog problems.

Jansen van Vuuren said usually in disaster plans the forensic facilities pool together resources to speed up postmortems reports. The report takes about four to five days and after that a body is released, but Jansen van Vuuren said it could be longer when there are mass casualties.

“The death investigation is much more difficult in a case where you have charred bodies. The greater the degree of charring the more difficult it is going to make the case.” 

He said the identification of charred remains was also difficult for the DNA processes. 

“Sometimes when a body is disfigured by an injury or decomposition or burning, in those kinds of conditions that is when we employ scientific methods of identification. One is the fingerprinting method, but if they are not on the South African database the fingerprinting method becomes difficult and sometimes impossible.”

Gauteng health department spokesperson Motalatale Modiba confirmed to TimesLIVE that families who reported missing relatives after the fire were from South Africa, Malawi, Tanzania, Zimbabwe and Lesotho. 

Jansen van Vuuren said when visual identification was not possible, the deceased was not on a local DNA database and there was no family relative available to assist with DNA processes, identification cannot be made. 

The deceased gets a pauper's burial if it could not be identified and no relative claimed the body. Jansen van Vuuren said this usually happened after three months,  depending on a municipal regulations 

“If there is a victim identification unit it would collect all the identification profile data including photographs of the face, clothing if that is available, tattoos and jewellery, things like that. They would collect fingerprints if those were available and data from DNA. They would take all that data and set up a profile of the victim. They keep these until there are family members who come to identify their loved ones.” 

Jansen van Vuuren said it would not be easy to identify the 62 bodies but unity and good communication among the different teams could speed up the process.

University of Cape Town (UCT) associate forensic medicine and toxicology professor Laura Heathfield told TimesLIVE extracting DNA from 62 samples, including cleaning the samples, would be time consuming.

“These are some of the most challenging cases to get DNA from and usually the samples that are available are in the form of hard tissue, like bones and teeth. It is tricky.

“The DNA extraction from samples is the longest in this process.”

Heathfiled estimated it would take five days in the UCT laboratory. This was not the final process. 

“We have to clean the samples first and be careful to make sure there is no cross contamination between the samples from people. Thereafter, once we have pure DNA we would determine how much DNA we were able to recover. At this stage we are able to determine if the DNA belongs to a male or female. Then we can do DNA profiling.” 

If the deceased’s identity exists in a local DNA database this made the process quicker, she said.

“It is important for blood relatives to come forward and provide these reference samples. If there are personal items of the deceased like a toothbrush or hairbrush that would be good for DNA reference but unfortunately these would be burnt in a fire. The family members can also provide DNA samples of their own to match the DNA. 

“This sample would be in the form of a buccal swab, taken inside a cheek. It does not hurt. We can use that to identify.” 

“Sometimes we need to process the DNA sample again and adjust some conditions to get the maximum amount of information from that sample. During the postmortem it is always a good idea to take a few samples for DNA testing and not only one because that one sample might not be able to yield the best results.” 

African Forensic Sciences Academy's  Dr Antonel Olckers told TimesLIVE mass disasters, where foreign nationals are involved, were not easy cases to solve. 

“It is a complex management task that involves various consulates, as well as aligning support efforts for loved ones of the deceased by, for example, obtaining DNA samples from families in other countries to assist in identifying the bodies of their loved ones.

“It is understandable that families seek answers about the cause of the disaster, and how they can be reunited with the bodies of their loved ones. This takes time and aspects such as treating the bodies of the dead with respect and dignity are key,” Olckers said.

“Many of the questions asked at this time can be answered by forensic science work if the scene of the disaster is handled appropriately, and evidence is collected in a manner that protects its integrity,” she said.