Trélex, Switzerland – February 2, 2025, began as a peaceful day for Mariann Vegh, but quickly spiraled into a parent’s worst nightmare when her five-month-old son, Erik, began convulsing and struggling to breathe after a morning walk.
“It only took eight minutes for help to arrive, but it seemed like an eternity,” recalls Mariann, a marketing director. “I can still hear my desperate voice calling Erik.”
The terrifying episode was the first sign of a profoundly rare genetic disorder. After weeks of tests – blood work and MRIs revealing nothing conclusive – a genetic test two months later delivered the diagnosis: asparagine synthetase deficiency (ASNSD). This hereditary condition, caused by a mutation in the ASNS gene, causes serious neurological problems and is passed down from both parents.
Doctors who treated Erik had never encountered ASNSD. A search online revealed a sobering statistic: only around 40 cases had been diagnosed worldwide, and none in Switzerland. Published research on ASNSD indicates that affected children often die before their first birthday.
Currently, there is no established treatment for ASNSD. While Erik, now 15 months old, is considered to have a milder form of the disease and receives medication to manage seizures, his prognosis remains uncertain. The condition can lead to blindness, developmental delays, and, in severe cases, death.
A Race Against Time for Ultra-Rare Disease Treatment
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Increasingly, parents are becoming the driving force behind research for conditions pharmaceutical companies overlook.
Refusing to accept a bleak outlook, Mariann embarked on a relentless search for answers, sending nearly 200 emails to doctors, rare disease organizations, and her network. She and her husband, Balázs Karancsi, became convinced that a cure was possible, but that they couldn’t afford to wait for someone else to find it.
The couple founded the ASNSD Research Association to connect with other families affected by the disease, raise funds, and centralize research efforts. They found a crucial ally in Roxane van Heurck, a geneticist at the University Hospitals of Geneva, who helped assemble a team of experts to explore potential research avenues.
Balázs and Mariann immersed themselves in drug design training, networked with scientists, and connected with families online, all while caring for Erik and their older son, Mark. They are also navigating complex insurance and medical costs and striving to raise 500,000 Swiss francs to launch research, with the ultimate goal of developing a gene therapy to correct the faulty ASNS gene.
Parents Leading the Charge
What Mariann and Balázs are experiencing is relatively uncommon in Switzerland, but increasingly prevalent in the United States. Experts estimate that only a handful of patients or caregivers in Switzerland have independently pursued treatment development for rare diseases.
This shift is fueled by growing desperation, easier access to fundraising platforms like GoFundMe, and advancements in medical research. There are over 7,000 known rare diseases, impacting at least 300 million people globally, yet only 5% have approved treatments. These treatments primarily address more common rare conditions, like cystic fibrosis.
Ultra-rare diseases, affecting fewer than 100 patients, often fall through the cracks for pharmaceutical companies. However, emerging technologies like gene therapy offer renewed hope. “Gene therapy changes the paradigm,” explains Bernard Schneider, a senior researcher at the Bertarelli gene therapy technology platform at the École Polytechnique Fédérale de Lausanne (EPFL), who collaborates with the couple. “These therapies were once considered too risky, but we’ve learned so much, and now we’re confident in their potential.”
A Growing Movement of Parent-Researchers
Mariann and Balázs aren’t alone in their quest. In 2017, in the United States, Nasha Fitter and Nicole Johnson established the FOXG1 Research Foundation to find a cure for FOXG1 syndrome, a rare genetic neurodevelopmental disorder.
The foundation, initially supported by European funding, has raised over $17 million (13.6 million francs). It has evolved into a global, parent-led NGO developing the first gene therapy for FOXG1 syndrome, funding a dedicated laboratory with 20 scientists and planning clinical trials for 2026.
Other parent-led organizations, such as the PACS2 Research Foundation and the SCN8A International Alliance, attract leading researchers, co-author peer-reviewed studies, and provide scientific guidance to families and doctors. Some, like Mila’s Miracle Foundation for Batten Disease in the United States, have even achieved treatment approval.
The Fight Continues for Erik
For Mariann and Balázs, the journey is far from over. Erik’s seizures are currently controlled with medication, but he is not reaching typical developmental milestones. “We have incredible support, but we desperately need to halt the disease’s progression,” says Mariann.
The couple acknowledges the challenges ahead and the uncertainty of developing a gene therapy in time to save their son’s life. Their research plan includes exploring repurposing existing therapies as a short-term solution for Erik.
Progress is being made. Their project has been accepted into the Genetic Therapy Accelerator Center at University College London, which is investigating gene therapy and antisense oligonucleotides (ASO). They are also collaborating with researchers in Switzerland, including Roxane van Heurck and Bernard Schneider.
The family has launched a crowdfunding campaign to raise 500,000 francs for research, hoping to generate data that will qualify them for larger grants.
“Things have changed,” says Roxane van Heurck. “Five years ago, we had nothing to offer parents of children with ultra-rare diseases. But the technology has evolved. The field is changing.”
