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J Pediatr Genet 2023; 12(03): 193-198
DOI: 10.1055/s-0043-1768693
Review Article

First Clinical Report of Two RAB3GAP1 Pathogenic Variant in Warburg Micro Syndrome

Nejmiye Akkuş 
1   Department of Medical Genetics, Faculty of Medicine, Tokat Gaziosmanpasa University, Tokat, Türkiye
,
Tuğba Akın Duman
2   Department of Medical Genetics, Haseki Training and Research Hospital, Ministry of Health, Istanbul, Türkiye
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Abstract

Warburg micro (WARBM) syndrome is an autosomal recessive disease characterized by severe brain and eye abnormalities. Loss-of-function mutations in RAB18, RAB3GAP2, RAB3GAP1, or TBC1D20 can lead to this disease. Here, we present two unrelated WARBM syndrome patients who had an RAB3GAP1 c.559 C > T, (p.Arg187Ter) and c.520 C > T (p.Arg174Ter) homozygous state. Both patients had microcephaly, microphthalmia, microcornea, bilateral congenital cataracts, severe intellectual disability, and congenital hypotonia. Using the method of next-generation sequencing and sanger sequencing, we found two nonsense variations at the splice site in exon 7 of RAB3GAP1 in the WARBM syndrome patients. The mutations were predicted to cause the syndrome due to the early stop codon, and the patients had the WARBM1 syndrome. We present the first clinical report of two different unreported variants with RAB3GAP1 mutation in the literature.

Keywords

RAB3GAP1 - Warburg micro syndrome - congenital cataracts - microcephaly - microphthalmia


Publication History

Received: 22 September 2021

Accepted: 10 April 2023

Article published online:
11 May 2023

© 2023. Thieme. All rights reserved.

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