ABCA7

ABCA7 (ATP-binding cassette sub-family A member 7) is a human gene encoding a membrane-associated transporter protein of the ATP-binding cassette (ABC) superfamily. Like other ABCA transporters, ABCA7 is predicted to have two transmembrane domains and two nucleotide-binding domains and functions to move lipids across cellular membranes.

Expression: ABCA7 is widely expressed, with notable levels in myeloid cells (including monocytes and macrophages) and in brain tissue, particularly in microglia.

Function: The protein participates in lipid homeostasis by mediating the cellular efflux of phospholipids and cholesterol to lipid-acceptor molecules such as apolipoproteins. In immune cells and the brain, ABCA7 also influences phagocytic uptake and processing of cellular debris and amyloid-beta, contributing to microglial clearance of aggregates.

Clinical significance: Genetic variation in ABCA7 has been associated with susceptibility to late-onset Alzheimer's disease in several genome-wide association studies and follow-up analyses. Both rare loss-of-function variants and certain common variants have been reported to modify risk, potentially through effects on lipid metabolism and microglial function. ABCA7 is a focus of research into mechanisms of amyloid clearance and neuroinflammation in Alzheimer's disease, and it is considered a potential target for therapeutic strategies aimed at enhancing microglial phagocytosis and lipid transport.

Genomic context: The ABCA7 gene is located on chromosome 19 in humans.