COL4A1

The encoded type IV collagen alpha protein functions as part of a heterotrimer that forms integral components of basement membranes and interacts with other extracellular matrix components including perlecans, proteoglycans, and laminins. Mutations cause autosomal dominant conditions including hereditary angiopathy with nephropathy, aneurysms and muscle cramps, brain small vessel disease with or without ocular anomalies, and pontine microangiopathy with leukoencephalopathy. The pathogenic mechanism involves loss of function, leading to compromised basement membrane integrity in cerebrovascular and other tissues.