Could SIDS gene clear mom?

After Kathleen Folbigg's four children died, she was sent to prison. In 2018, her solicitors requested genetic testing.

Dave Yasvinski 5 minute read March 22, 2021
SIDS

SIDS has been linked to a specific gene that regulates calcium in the heart. Getty

Kathleen Folbigg made headlines around the world in 2003 when she was sentenced to 40 years in prison for the deaths of her four small children. Now, some experts believe the horrific deaths — which earned the inmate the title of Australia’s worst female serial killer — may have been caused by a rare genetic condition that Folbigg’s children shared with their mother.

Folbigg was sent to prison in 2003 for the murders of Patrick, Sarah and Laura and the manslaughter of Caleb, all of whom were between the ages of 19 days and 18 months at the time of death, according to CNN. A jury concluded the children — who all died in their sleep — had been smothered to death by their mother. Genomic testing conducted in 2020, however, revealed the children may have actually died from complications caused by genetic mutations.

In response to the finding, a group of 90 scientists, including two Australian Nobel Laureates, have signed on to a petition calling on the governor of New South Wales to pardon and release the imprisoned mother.

Sudden infant death syndrome is an umbrella term used to describe the unexplained death — usually while sleeping — of a healthy baby who is less than a year old, according to the Mayo Clinic. SIDS is the leading cause of death in infants between the ages of one and 12 months of age, although the majority of deaths occur between months two and four. Roughly one in 2,000 Canadian children die from SIDS every year. While the cause of death is typically unknown, it is believed that genetic factors may play a role in the devastating deaths.

When Folbigg was sentenced in 2003, genetic testing was in its infancy. By 2018, the situation had changed considerably, according to Carola Vinuesa, a professor and co-director at the Centre for Personalised Immunology at the Australian National University. At the request of Folbigg’s solicitors, Vinuesa was part of a team that conducted genetic testing on the mother. A cheek swab found Folbigg possessed a previously unreported mutation of the CALM2 gene. This gene, which is responsible for controlling the movement of calcium in and out of heart cells, is one of the most recognized causes of SIDS, Vinuesa said.

This finding would eventually lead her team to conduct genetic sequencing of 20 year old blood samples from Folbigg’s children. They found the girls possessed the same mutation to the CALM2 gene, known as variant G114R. “We concluded this variant likely contributed to the natural deaths of the two girls by altering the heart’s normal rhythm, Vinuesa said. “This may have been triggered by infections both girls had around the time they died and the medication they were given, which combined with their mutation, made them particularly susceptible to heart complications.”

While the two boys did not possess that particular genetic mutation, they had others that may be indicative of a death from natural causes, Vinuesa said. “Only recently, as we were re-analysing the Folbigg genomes, we found the two boys had two different novel and rare variants in a gene known as BSN (or Bassoon), one inherited from their mother and the other presumably inherited from their father.

“This is a gene that, when defective in mice, causes early onset lethal epilepsy — mice die young during epileptic fits. We are currently investigating whether the variants found in the Folbigg boys can cause disease.”

Vinuesa said it is likely that the rarity of such mutations worked against the suspect at the time of her conviction and again in 2019 during an inquiry into the case that Vinuesa participated in. “In this case, and as far as I can tell, Folbigg was selected for investigations because of the rarity of the events, with circumstantial evidence gathered from interpretations of her diaries presented as evidence of her guilt. Such an approach forgets that rare events do occur. And in genetics, one-off events are commonplace.

“Then there was the notion of expertise. In the lead-up to the inquiry, I was expecting subject matter experts to be called to give evidence. But there was not a single expert in the genetics of heart arrhythmias, nor an expert in CALM genes.”

Indeed, at her trial in 2003, the prosecution leaned heavily on a commonly cited maxim from British pediatrician Roy Meadow: “One sudden infant death is a tragedy, two is suspicious and three is murder, until proven otherwise.”


Regardless of whether or not Folbigg wins a pardon and regains her freedom, advances in genetic testing may soon provide answers and, perhaps, some measure of closure to other parents dealing with the sudden loss of a child. “In most families where there have been SIDS deaths, nobody has yet gone back and sequenced the genomes of the children,” Vinuesa said.

“That could help families looking for answers — and also help those worried about being targeted by the law.

“Many families live in fear, because they’ve had two or more children dying and they’re worried that one day someone will be knocking at their door with some type of police investigation,” she said. “We know now that when you have a genetic condition … it’s not rare.”

Dave Yasvinski is a writer withHealthing.ca

Don’t miss the latest on COVID-19, reopening and life. Subscribe to Healthing’s daily newsletter COVID Life.

Comments

Postmedia is committed to maintaining a lively but civil forum for discussion and encourage all readers to share their views on our articles. Comments may take up to an hour for moderation before appearing on the site. We ask you to keep your comments relevant and respectful. We have enabled email notifications—you will now receive an email if you receive a reply to your comment, there is an update to a comment thread you follow or if a user you follow comments. Visit our community guidelines for more information and details on how to adjust your email settings.