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Review
. 2023 May 11;12(3):193-198.
doi: 10.1055/s-0043-1768693. eCollection 2023 Sep.

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

Nejmiye Akkuş  1 , Tuğba Akın Duman  2
Affiliations
Review

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

Nejmiye Akkuş et al. J Pediatr Genet. .

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.

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Conflict of interest statement

Conflict of Interest None declared.

Figures

Fig. 1
Fig. 1
( A ) Photograph of case 1. ( B ) Pedigree of family of case 1. In family pedigrees, roman numerals indicate generation number, and arrows indicate proband.
Fig. 2
Fig. 2
Sequence electropherograms of case 1 and his family.
Fig. 3
Fig. 3
Case 2, magnetic resonance imaging scans, showing thin corpus callosum and cerebral atrophy.
Fig. 4
Fig. 4
( A ) Photograph of case 2. ( B ) Pedigree of family of case 2. In family pedigrees, roman numerals indicate generation number, and arrows indicate proband.
Fig. 5
Fig. 5
Sequence electropherograms of case 2 and her family.
See this image and copyright information in PMC

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