Whole exome sequencing identified a novel heterozygous variant of COL4A5 NM_033380.3: c.2636 C > A (p.S879*) and a rare variant of GCK NM_001354800.1: c.1135 G > A (p.A379T) as the causes of Alport syndrome and monogenic diabetes, respectively. Here, COL4A5 is linked to diabetes mellitus.