Novel mutation in OCRL leading to a severe form of Lowe syndrome

Int J Ophthalmol. 2019 Jul 18;12(7):1057-1060. doi: 10.18240/ijo.2019.07.01. eCollection 2019.

Abstract

Aim: To investigate the phenotype and genotype of a family with X-linked recessive Lowe syndrome.

Methods: All the members in the Chinese pedigree underwent comprehensive ophthalmologic and systemic examinations. Genomic DNA was isolated from peripheral blood of the pedigree members and 100 unrelated healthy Chinese subjects. Direct sequencing was performed to screen the exons and intron boundaries of OCRL.

Results: The ophthalmological and systemic examinations suggested that the affected individual had Lowe syndrome. The phenotype in the pedigree is severe and consistent among all the affected individuals except for an individual who additionally suffered from congenital heart disease and laryngeal cartilage dysplasia. Directional Sanger sequencing identified a complex mutation c.(2368_2368delG; c.2370A>C) in the Rho-GTPase activating protein domain. This complex mutation causes termination of protein synthesis at amino acid 824 and result in a new peptide with 823 amino acids (p.Ala790ProfsX34). This mutation was not detected in 100 unrelated healthy Chinese subjects.

Conclusion: Our findings expand the phenotypic and genotypic spectrum of Lowe syndrome.

Keywords: Lowe syndrome; OCRL; congenital membranous cataract; oculocerebrorenal syndrome.