Hereditary cerebral amyloid angiopathy is a condition characterized by an abnormal buildup of protein clumps called amyloid deposits in the blood vessels in the brain, causing vascular disease (angiopathy). People with hereditary cerebral amyloid angiopathy often have progressive loss of intellectual function (dementia), stroke, and other neurological problems starting in mid-adulthood. Due to neurological decline, this condition is typically fatal in one's sixties, although there is variation depending on the severity of the signs and symptoms. Most affected individuals die within a decade after signs and symptoms first appear, although some people with the disease have survived longer.

Variants (also called mutations) in the APP gene are the most common cause of hereditary cerebral amyloid angiopathy. APP gene variants cause the Dutch, Italian, Arctic, Iowa, Flemish, and Piedmont types of this condition. Variants in the CST3 gene cause the Icelandic type. Familial British and Danish dementia are caused by variants in the ITM2B gene.

The prevalence of hereditary cerebral amyloid angiopathy is unknown. The Dutch type is the most common, with over 200 affected individuals reported in the scientific literature.

Hereditary cerebral amyloid angiopathy caused by mutations in the APP, CST3, or ITM2B gene is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder.

Published Date: April 11, 2022
Published By: National Institutes of Health