Based on the clinical phenotypes, the predicted influence on proteins, and considerations from the literature, we identified a novel heterozygous variant of COL4A5 NM_033380.3: c.2636 C > A (p.S879*) and a rare heterozygous variant of GCK NM_001354800.1: c.1135 G > A (p.A379T) as the causes of Alport syndrome and diabetes, respectively. The gene discussed is COL4A5; the disease is Alport syndrome.