Impact of the -675 4G/5G polymorphism of the plasminogen activator inhibitor-1 gene on childhood IgA nephropathy.

Plasminogen activator inhibitor-1 (PAI-1) is an important regulator of the fibrinolytic pathway and extracellular matrix (ECM) turnover. The -675 4G/5G polymorphism in the PAI-1 promoter is associated with altered PAI-1 transcription, suggesting that this polymorphism may be a candidate risk factor for diseases characterized by ECM accumulation, such as immunoglobulin A nephropathy (IgAN) and mesangial proliferative glomerulonephritis (MesPGN). We genotyped childhood patients with biopsy-confirmed IgAN (n=111) and MesPGN (n=47), and healthy control subjects (n=230) for the -675 4G/5G PAI-1 polymorphism by polymerase chain reaction-restriction fragment length polymorphism methods.