According to the LOVD database, in Alport syndrome, affecting millions of people worldwide, over two thousand genetic variants are known in the COL4A3, COL4A4, and COL4A5 genes that encode the α3, α4 and α5 chains of the Col-IVα345 scaffold, and this number is growing (4, 5, 45, 46, 47) (Fig. 1). Here, COL4A4 is linked to Alport syndrome.