Neurologists at a memory clinic in Beijing have diagnosed a 19-year-old with probable Alzheimer's disease, making him the youngest person ever to receive the diagnosis without known genetic mutations.
The teen began experiencing memory decline around age 17, struggling to focus in class and recall recent events. Brain scans showed hippocampal shrinkage, and cerebrospinal fluid analysis revealed Alzheimer's biomarkers.
Unlike most early-onset cases-which are linked to inherited gene mutations like PSEN1-this patient had no family history of dementia. A genome-wide search found no usual suspect mutations.
"This is altering our understanding of the typical age of onset," said neurologist Jianping Jia. His short-term memory scores were 87% lower than peers. The case, published in the Journal of Alzheimer's Disease, underscores the disease's complexity and the need to explore early-onset mysteries.