Genetic studies of IgA nephropathy: what have we learned from genome-wide association studies.

Primary IgA nephropathy (IgAN) is the most common glomerulonephritis in the world. It is most common in Asian populations, followed by Caucasians, yet relatively infrequent amongst African populations. The striking difference in the prevalence of IgAN between world populations, together with the known familial aggregation of disease, suggests an inherited mechanism. Recently three genome-wide association studies (GWAS) of IgAN have identified seven susceptibility loci, providing initial insight into the genetic architecture of this trait. While genetic studies of complex traits are challenging, applying new techniques and methods of analysis, especially Next-Generation Sequencing, will push the genetic studies of IgAN forward.