A newly published study in the journal Cell details a newly discovered mechanism of neuron death triggered by a rare genetic mutation in children, offering potential insights into the fight against more common neurodegenerative diseases. Researchers pinpointed a process called ferroptosis – cell death caused by iron accumulation and membrane damage – as a key factor in the rapid brain deterioration seen in patients with Sedaghatian spondylometaphyseal dysplasia (SSMD), a condition affecting only a few dozen people worldwide [[1]]. The findings suggest this pathway may also play a role in Alzheimer’s, Parkinson’s, and Huntington’s diseases, opening new avenues for therapeutic research [[1]].
A rare genetic mutation in children triggers neuron death through a newly discovered mechanism, according to a new study with implications for understanding neurodegenerative diseases like Alzheimer’s and Parkinson’s.
FOTO Shutterstock
While dementia is typically associated with aging, rare forms of childhood dementia exist, linked to over 100 different genetic diseases. Analyzing these dramatic cases is providing researchers with crucial insights into how neurodegeneration develops, a process central to understanding conditions like Alzheimer’s and Parkinson’s disease.
Recent experiments focusing on an extremely rare genetic mutation linked to severe neurodegeneration in children have identified a new mechanism that triggers neuron death. The findings suggest that similar pathways of cellular demise may be involved in other brain diseases, including Alzheimer’s, Parkinson’s, and Huntington’s disease.
How the Study Was Conducted
Researchers at the Helmholtz Munich research center in Germany led the study, demonstrating that mutations in a single gene cause progressive inflammation and neuronal death in mice. Similar patterns of cell death were observed in human brain cells grown in the lab, derived from skin cells of patients with the same mutation.
The specific form of cell death identified is called ferroptosis, a type of programmed cell death triggered by iron accumulation and oxidative damage to the cell membrane. Analysis of proteins expressed by neurons revealed that this mechanism resembles processes previously described in dementia, and recent evidence has already linked ferroptosis to Alzheimer’s disease.
The genetic condition studied, known as Sedaghatian spondylometaphyseal dysplasia (SSMD), is exceptionally rare, characterized by severe abnormalities of the brain and skeleton. First described in 1980, only a few dozen cases have been officially reported since, many involving the death of children within the first few months of life.
What Researchers Discovered
Genomic sequencing revealed that SSMD is linked to mutations in the gene encoding the GPX4 enzyme, considered a “protector” against ferroptosis because it defends cell membranes from oxidative damage. While mutations in this gene don’t necessarily lead to early-onset dementia, experiments on mouse cells and lab-grown “mini-brains” demonstrate how GPX4 protects neurons and how its dysfunction can lead to cell death.
The research focused on three children with SSMD from the United States, who exhibited varying degrees of brain atrophy and mutations in the same functional region of the GPX4 gene. Data from these cases was then used for further studies on animal models and nerve cells obtained from a patient’s skin cells.
Marcus Conrad, director of the Institute of Metabolism and Cell Death at Helmholtz Munich, explained that the GPX4 enzyme normally anchors to the cell membrane and rapidly neutralizes lipid peroxides as they form. In the studied mutation, this “anchor” is missing, preventing the enzyme from fulfilling its protective function for neurons.
Neurons grown in the lab from stem cells of patients with SSMD proved particularly vulnerable to ferroptosis. Blocking this process with an experimental chemical compound slowed neuronal death in mice and cell cultures. Researchers emphasize that these substances are not yet approved for clinical use.
Dementia research has long focused on protein deposits in the brain, such as beta-amyloid plaques, but this study shifts attention to cell membrane damage as an initial event in neuronal degeneration. This finding could open new avenues for therapeutic intervention.
The study’s authors noted that establishing the link between an enzyme’s structural characteristic and a severe human disease required nearly 14 years of research, highlighting the importance of long-term funding for basic research and international multidisciplinary collaboration.
The study was recently published in the journal Cell.
