[Analysis of Alport syndrome induced by type IV collagen alpha 5 gene mutation in two families].

OBJECTIVE: To investigate genetic characteristics of Alport syndrome. METHODS: High-throughput sequencing-based whole exome sequencing was performed in two patients with recurrent unexplained abnormal urinalysis. The pathogenicity of the genetic variations, type of Mendelian genetics, and clinical phenotypes were analysed, and the disease-cause mutations were confirmed in the family members using Sanger sequencing. RESULTS: Two heterozygous splice site mutations of COL4A5 gene c.2147-2A > T (IVS27) and c.646-2A > G (IVS11) (NM_033380) were found in patients of the two families, which showed a co-segregation association with the affected members of the families. CONCLUSIONS: Alport syndrome is mainly inherited from direct female patients, and prenatal genetic screening based on amniotic fluid testing can effectively prevent birth defects in patients with a family history of this characteristic phenotype.