This rare mitochondrial genetic condition that affects the optic nerve causes rapid, severe central vision loss, often in early adulthood. It leads to life-changing impacts on daily living, emotional wellbeing and independence.

Because LHON is inherited through the mothers’ line and affects each carrier differently, families often face uncertainty about who may be impacted and when.

“There is a ripple effect with LHON,” says Dr Sandra Staffieri AO, Research Fellow from the Clinical Genetics Unit at CERA.

“It not only impacts the person who experiences the sudden vision loss, but also the people around them – their partner, their mother who feels guilty they have passed the condition on, and their siblings who await potentially the same fate.” CERA’s Dr Isabel Lopez Sanchez, Head of Mitochondrial Biology and Disease, says this unpredictability is at the heart of the LHON experience.

“The uncertainty of having the genetic risk creates great anxiety for families, but it also highlights why the researcher-family relationship is so crucial as we need initial detailed information and then follow-up data.” In Australia, this relationship is particularly strong. The national LHON Research Team—including CERA Honorary Professor David Mackey AO — has spent more than 35 years working with over 100 families. It includes CERA’s Lisa Kearns, Dr Staffieri and Dr Lopez Sanchez.

Their deep partnership, involving more than 350 people led to their nomination for the Patients Australia Outstanding Patient Research Award for improving diagnosis, counselling and treatment.

“I first encountered a young man who had lost vision from LHON when I was a medical student in Hobart,” says Professor Mackey.

“His story stuck with me so eight years later I chose to research the genetics and epidemiology of LHON in Australia as my doctorate thesis with the University of Melbourne.”

Family values

Families play an active role in raising awareness and advocating for research, while researchers support them with accurate, contextual information — especially vital in an era where online searches often present confusing or alarming claims.

Recent Australian-led research has helped reshape the global understanding of LHON.

For decades, it was widely believed that half of all men and 10 per cent of women with a LHON genetic change would lose vision.

“Our seminal work showed the actual risk is much lower – one in six for men and one in 20 for women,” Dr Lopez Sanchez says.

“The discovery has changed our understanding of LHON and how families are counselled worldwide, reducing fear and providing clarity.”

In 2025, the team published two papers emphasising how important accurate genetic counselling can be for families affected by LHON. Their work also aimed to raise awareness of LHON among health professionals and to challenge misconceptions, as the condition can sometimes be mistaken for other eye diseases.

A significant new development is mitochondrial donation, an emerging reproductive technology which can help women with mitochondrial disease have genetically related children with a far lower chance of passing on the condition.

“This technology offers new opportunities for families, and genetic counselling helps them explore their options and feel supported in making family planning decisions that are right for them,” Ms Kearns says.

The LHON research team is working closely with Australia’s mitoHOPE pilot program, which will begin recruiting participants in late 2026.

This story was originally published in Creating the future in sight: Annual Review 2025.