Warburg Mikro Sendromu ile İlişkili TBC1D20 Geninde Yeni Bir Mutasyon

Amaç: Warburg mikro sendromu (WARBM) RAB3GAP1, RAB3GAP2, RAB18 ve TBC1D20 genlerindeki mutasyonlara bağlı olarak nadir görülen otozomal resesif bir hastalıktır. Sendrom mikrosefali, konjenital katarakt ve mikrokornea gibi oküler bulgular, ağır entellektüel gerilik ve hipogonadizm ile karakterizedir. Olgu: Takipleri sırasında WARBM tanısı konulan 3 yaşında bir erkek çocuğu sunuyoruz. Hastanın genetik analiz sonuçları, TBC1D20 geninde ekzon 3’te patojenik ve WARBM 4 fenotipi ile korele olan bir homozigot mutasyonu (c.259_260delinsCAC; p. Lys87HisfsTer42) ortaya çıkardı. Ebeveynlerin mutasyonu heterozigot olarak taşıdığı gösterildi. Sonuç: WES analizi WARBM’li akraba bir Türk ailesinde TBC1D20 geninde muhtemel patojenik yeni bir mutasyon (c.259_260delinsCAC) gösterdi ve WARBM tanısını koymamızı sağladı.

A Novel Mutation in the TBC1D20 Gene with Associated Warburg Micro Syndrome

Aim: Warburg micro syndrome (WARBM) is a rare autosomal recessive disorder due to mutations in the RAB3GAP1, RAB3GAP2, RAB18, and TBC1D20 genes. The syndrome is characterized by microcephaly, ocular findings such as congenital cataract, microcornea, severe intellectual disability, and hypogonadism. Case: We present a 3-year-old boy who was diagnosed with WARBM during follow-up.The genetic analysis of the patient revealed a pathogenic mutation (c.259 260delinsCAC (p. Lys87HisfsTer42) in exon 3 of the TBC1D20 gene, which correlates with WARBM 4. Their parents were shown to carry the mutation heterozygously. Conclusion: The WES analysis of a consanguineous Turkish family with WARBM showed a novel mutation (c.259_260delinsCAC) in TBC1D20 gene that is most likely pathogenic and allowed us to make the diagnosis of WARBM.

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