A piece of skin, some tissue and bone. Sometimes, hair. That’s all Dr Munro Marx and his team had to help bring closure to over 100 families locked in an interminable wait for their family members’ remains.
And even then, the 116 samples were so badly degraded that piecing together the identities of the victims of the Nigerian church tragedy was virtually impossible.
The searing heat of Lagos and a chemical preservative its coroners used nearly destroyed vital DNA.
“You must remember that when the tragedy happened, it took four to five days before the recovery of the bodies started,” explains Marx, who heads Unistel Medical Laboratories, a dedicated human and animal genetics testing centre at Stellenbosch University.
“In the temperatures and humidity of Lagos, decomposition happens pretty fast. So when they recovered the bodies they embalmed them.”
That’s a problem for DNA profiling because embalmment uses chemicals like formaldehyde, which penetrates tissues and cells.
“Once any tissue, or even bones, is treated that way, obtaining DNA is extremely difficult.
“The 116 samples that we got were really not at all of a good quality.”
It was in early October when the chief medical examiner in Lagos contacted Marx to obtain DNA from the victims of the Synagogue Church of All Nations collapse, which killed 116 people, including 84 South Africans.
A few days later, his lab received all 116 samples – each numbered.
“Now you have DNA profiles but you don’t know who’s who.
“You need family members or relatives so you can match these relations to a DNA profile.”
It was up to the government’s disaster management team, which comprised officials from the Health Department, and the SA Police Service, to collect DNA profiles from victims’ families.
For Unistel’s senior team of five geneticists, the meticulous, intricate work of processing the samples would start at 6am. It would end much later, when weary and exhausted, the scientists would leave the lab, often near midnight.
“You are matching, analysing, going back to the raw data, coming back and having a look again, trying to obtain more information. You get to the stage where you see everything, and you see nothing. Then… you have to start all over again. It was extremely stressful. We were working almost round the clock every day. We were under extreme pressure.”
Extracting DNA from the samples was labour intensive – and robots helped Marx’s team too.
“It’s trial and error. When you got the DNA at the right concentration and quality, you have DNA markers, which you synthetically amplify using a kit. Some samples worked with some kits, some with others. It was very much mix and match.
“We were working with a less than ideal quality of samples,” he said.
- Pretoria News Weekend