early-onset familial Alzheimer disease

pathology

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July 20, 2026

Quick Summary

Early-onset familial Alzheimer disease is a rare, inherited form of Alzheimer's that affects individuals in their fourth and fifth decades of life. It is characterized by a progressive decline in memory and cognitive abilities. The pathology involves the destruction of neurons and neural connections in the brain, leading to a decrease in brain mass. Key hallmarks include the presence of neuritic plaques, which are deposits of amyloid beta-protein fragments, and neurofibrillary tangles, which are twisted fibers of the tau protein, found within neurons. Genetic mutations on chromosomes 1, 14, and 21 are linked to these early-onset familial forms.12

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Alzheimer disease
Stages of the disease
These cases, referred to as early-onset familial Alzheimer disease, appear to result from an inherited genetic mutation. The majority of cases of Alzheimer disease, however, develop after age 60 (late-onset) and usually occur sporadically—i.e., in individuals with no family history of the disease—although a genetic factor has been identified that…
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These cases, referred to as early-onset familial Alzheimer disease, appear to result from an inherited genetic mutation. The majority of cases of Alzheimer disease, however, develop after age 60 (late-onset) and usually occur sporadically—i.e., in individuals with no family history of the disease—although a genetic factor has been identified that…
Read More