Altuğ KOÇ, Tayfun ÇİNLETİ, Ayfer ÜLGENALP, Özlem GİRAY BOZKAYA, Gizem YILDIZ, Elçin BORA, Meral TORUN BAYRAM

Initial Next-Generation Sequencing (NGS) Results of Alport Syndrome

Objectives: We have no series report concerning genetic etiology of Alport Syndrome (AS) in our country. So, we aimed to investigate ASrelated pathogenic variants of COL4A3, COL4A4 and COL4A5 genes in index cases and their families who referred to our center.Patients and Methods: The study includes 32 subjects (17 index cases and their relatives) who are investigated between years 2018-2019 byNGS targeting the coding regions of related genes. The test results and clinical findings of the cases are studied retrospectively.Results: By the presented study, 19 individuals identified to have COL4A3 and COL4A5 variations which could be important for the clinicalmanagement. In four cases, there are novel variants. In two cases, there are digenic variations. There is no clinically relevant variant in COL4A4gene. The most frequent three mutations of COL4A5 gene reported in United States (US) are not determined in our study group.Conclusion: The diagnostic genetic tests of AS should be designed to include whole coding regions of COL4A3 and COL4A5 genes, not justfor the frequently reported pathogenic variants. The cases without pathogenic variants by sequencing should be investigated for deletions/duplications of COL4A5 gene. Clinical findings of our cases with novel genetic variants are presented as a contribution to literature.

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