‘Likely’: Why Folbigg could be cleared after bombshell discovery

Researchers say it’s likely two of Kathleen Folbigg’s daughters died due to a rare mutation, as the convicted killer fights to be freed after 19 years in jail.

The rare genetic mutation Kathleen Folbigg passed onto her two daughters likely caused their deaths, world-leading scientists who have published cutting-edge research on the topic have told an inquiry.

An inquiry is examining the death of Folbigg’s four children as she seeks to be pardoned and released from prison after serving 19 years behind bars for a crime she says she didn’t commit.

She was convicted of the murder of her children Patrick, Sarah and Laura and the manslaughter of her son Caleb, who all died between 1989 and 1999.

Folbigg, 55, has consistently denied smothering her children in their sleep and following a petition from her supporters, the NSW government announced an inquiry into the matter.

New expert medical evidence published in March raised questions about her guilt, after it showed Sarah and Laura Folbigg inherited a genetic mutation – known as CALM2 G114R – which can cause cardiac problems and lead to sudden death.

Kathleen Folbigg is fighting to be pardoned. Picture: AAP / Peter Rae

Professor Michael Toft Overgaard – one of two Danish genetic experts appearing before the inquiry on Tuesday – was part of the team which discovered the first CALM mutation in 2012 and has co-authored 15 papers on the topic.

In a report prepared for the inquiry, he and Professor Mette Nyegaard concluded the CALM2 G114R variant was enough to have caused the death of Folbigg’s two daughters.

Counsel assisting the inquiry Julia Roy asked him: “Would you say if it was likely that the girls died by reason of the variant?”

“From what we know, yes,” Professor Overgaard said.

“As we write, we think it is likely that this mutation could have caused the deaths.”

Professor Nyegaard added: “From where we stand and what we can see … it looks like a bad variant.”

Folbigg failed to have her convictions quashed during two unsuccessful appeals and a public inquiry in 2019 again reinforced her guilt.

The fresh inquiry is being heard by retired NSW Supreme Court justice Tom Bathurst QC, with a report to be prepared before the governor as she asks to be pardoned.

Folbigg’s barrister, Gregory Woods QC, previously told the inquiry it could not be “properly excluded” that the girls’ deaths were caused by the CALM2 G114R mutation.

“It was regarded in the scientific community that up until 2012, variations in calmodulin were incompatible with life,” Professor Overgaard said.

Kathleen Folbigg with daughter Laura. Picture: Supplied

The inquiry has been told that every heartbeat depends on a complex chain of openings and closings of muscles and the passage of calcium, sodium and potassium.

The inquiry further heard that the opening and closing of those channels is affected by the calmodulin protein.

“They had a hard time believing we really identified a person or a family with a variant,” Professor Mette Nyegaard told the inquiry.

Each of Folbigg’s four children died in their sleep in the family’s Hunter Valley home and were discovered by Folbigg.

In 2005, following an appeal, her sentence was reduced from 40 years to 30 years and she will first be eligible for parole in April 2028.

During her trial, the prosecution argued Folbigg killed her four children by smothering them, but she has maintained they died of natural causes.

The inquiry was due to continue for another week, however has been delayed because of fresh scientific evidence, and will now resume in February.