Autosomal recessive Alport syndrome caused by a novel COL4A4 compound heterozygous mutation: A case report

Autosomal dominant inheritance of Alport syndrome (AS) is very rare, and only a few unrelated families have been found with COL4A3 or COL4A4 gene mutations. Therefore, we aimed to explore the COL4A4 gene mutation spectrum in autosomal recessive Alport syndrome (ARAS).Blood samples of the proband and his parents were sent to the Institute of Rare Diseases at the West China Hospital of Sichuan University for genetic testing. The analyzed genes were COL4A3-5. The chip capture high-throughput sequencing method was adopted. The data analysis process of high-throughput sequencing was applied for data analysis.A 26-year-old female patient (proband) was diagnosed with AS. The results of genetic analysis and comparison between the proband's genetic information and her parents' showed that the proband carried a compound heterozygous mutation c.4758_4760delCCC (p.1586_1587del) and c.4333+3A>G in the COL4A4 gene; the nonframeshift mutation c.4758_4760delCCC (p.1586_1587del) was inherited from her mother, and the splice site mutation c.4333+3A>G was inherited from her father, suggesting that COL4A4 gene variants caused ARAS in this patient.The novel mutation found in this patient enriches the mutation spectrum of ARAS caused by the COL4A4 gene.