The scientist who uncovered new evidence casting doubt on Kathleen Folbigg's guilt says she is just following the science, and had never heard of the woman convicted of killing her four children until she began work on her case.

Carola Vinuesa, a leading researcher and professor of immunology and genomic medicine at the Australian National University in Canberra, discovered a previously-unknown gene mutation in Folbigg and her two daughters, Laura and Sarah, which is strongly linked to sudden death in children and babies.

Professor Vinuesa was also responsible for recruiting the 90 eminent scientists and researchers, including two Nobel laureates, who last week put their names to an extraordinary petition calling for Folbigg to be pardoned and freed from jail.

Folbigg, from the Hunter Valley, was convicted in 2003 of smothering her four children - Patrick, Sarah, Laura and Caleb - but had always maintained her innocence and was convicted despite no forensic evidence that the children had been smothered. A number of court appeals against her convictions have failed and she is 18 years into a 30-year jail term.

Spanish-born Prof. Vinuesa, who arrived in Australia in 2000, had never heard of Folbigg until she was approached by Folbigg's barrister Isabelle Reid in 2018, and had to do internet searches to learn who she was.

Professor Carola Vinuesa who found the new medical evidence.
Professor Carola Vinuesa who found the new medical evidence.

She said the evidence she and a team of experts uncovered was "black and white.''

"This is about science being taken seriously,'' she said.

"It's not about Kathleen Folbigg, although of course it would be good if justice was done.

"So it's a bigger issue, it's about science and the law, it's about this particular technology but it's also about ensuring that science is weighed properly, so that's what I think motivates many of us (the signatories to the petition).''

Ms Reid asked Prof. Vinuesa if she was aware of any developments in genetic research since the 2003 trial.

Prof Vinuesa's laboratory was doing similar work identifying genomes in patients with various diseases, and she agreed to sequence Kathleen Folbigg's genomes as a starting point.

"It was a bit of a long shot but given that many of these conditions are inherited it is likely that if there was to be a genetic mutation it would have been inherited from the mother or the father or both,'' she said.

Prof. Vinuesa and colleague Dr Todor Arsov led the research, with Dr Arsov visiting Folbigg at Sydney's Silverwater Women's Correctional Centre to take a saliva sample and use a Buchal swab to take cell samples from inside her mouth.

Kathleen Folbigg appears on a video link screened a the NSW Coroners Court.
Kathleen Folbigg appears on a video link screened a the NSW Coroners Court.

Their work revealed Folbigg had a previously-unknown mutation in the CALM2 gene, which was known to cause sudden cardiac death.

They then asked the Victorian Clinical Genomics Service to sequence the genomes of the four Folbigg children, using samples which were up to 20 years old, which identified the same mutation in the two Folbigg girls, inherited from their mother.

Further research is underway into the two little Folbigg boys.

Prof. Vinuesa reached out to Professor Peter J. Schwartz, a world-leading authority on genetic causes of sudden deaths, who is head of the Center for Cardiac Arrhythmias of Genetic Origin in Italy.

"I was surprised when I got a letter from Peter Schwartz and he told me, 'look this is a pure coincidence but we just published a paper where we found a very similar mutation … very similar but not identical but being so similar this mutation has caused the death of a girl in the US and the cardiac arrest of her brother'.


Murder victim Caleb Folbigg.
Murder victim Caleb Folbigg.


"So he said at that point 'I think this one is likely pathogenic'' and when you say likely pathogenic, it means it has a high probability of causing death. So he agreed to submit a letter to the inquiry, I submitted it on his behalf.''

The inquiry was being conducted by QC and former judge Reginald Blanch. However Mr Blanch declined to re-open his inquiry, and instead upheld Folbigg's conviction.

Prof. Vinuesa said she had been "a little bit unsatisfied'' at the Blanch inquiry because there had been no cardiac geneticist involved.


Murder victim Laura Folbigg.
Murder victim Laura Folbigg.

"I thought we might be missing something, myself being no expert in cardiac genetics.''

She pushed on, contacting another international expert, Professor Michael Toft Overgaard from Denmark, who joined Prof Vinuesa and 25 other experts to continue their investigations.

"Then when that evidence came through and it was black and white and it showed this particular mutation was as damaging … as others that have been shown to be lethal in children.

"That paper was put together, was peer reviewed in a scientific journal and that constitutes additional, very strong evidence, that this mutation is probably the cause or a cause of natural death in the children that have it.''

The 90 experts who signed a statement of scientific consensus this week include Nobel laureates Professor Peter Doherty and Emeritus Professor Elizabeth Blackburn, and scientists Professor Ian Frazer and Professor Fiona Stanley.

Prof. Vinuesa said it took less than 10 days to get almost 100 names for the petition, which was lodged with NSW Governor Margaret Beazley on Tuesday.

"The science was very strong, it wasn't actually hard,'' she said of the approaches made to the experts.

"I'm sure if we had gone for 100 days we would have got thousands.''



Originally published as How killer mum Folbigg's saliva swab led to genetic twist

Murder victim Patrick Folbigg with father Craig.
Murder victim Patrick Folbigg with father Craig.
Murder victim Sarah Folbigg.
Murder victim Sarah Folbigg.