Up to 40% of patients with C3GN and up to 33% of patients with DDD have detectable genetic abnormalities in AP genes such as C3, CFB, CFH, CFHR, CFI, MCP (CD46), and THBD, including variants of unknown significance (Table 1).6, 7, 8,19,20,38,39 Rare pathogenic, or likely pathogenic, variants in genes of the AP are present in a much smaller proportion of patients with C3G (∼17%–35%)7,12,20,38,39; the presence of these variants in patients with atypical hemolytic uremic syndrome is higher, at approximately 51%.46 This evidence concerns the gene CD46 and atypical hemolytic-uremic syndrome.