If every person with a heterozygous COL4A3 or COL4A4 mutation were labelled with the diagnosis of Alport syndrome, its incidence would increase from the current level of 1 in 5–10,000 to as high as 1 in 100 [23, 24], with ESKD being uncommon. The gene discussed is COL4A4; the disease is Alport syndrome.