Publications by authors named "Robyn Rautenbach"

LOXL1 (lysyl oxidase-like 1) has been identified as the major effect locus in pseudoexfoliation (PEX) syndrome, a fibrotic disorder of the extracellular matrix and frequent cause of chronic open-angle glaucoma. However, all known PEX-associated common variants show allele effect reversal in populations of different ancestry, casting doubt on their biological significance. Based on extensive LOXL1 deep sequencing, we report here the identification of a common non-coding sequence variant, rs7173049A>G, located downstream of LOXL1, consistently associated with a decrease in PEX risk (odds ratio, OR = 0.

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We report the histopathological and ultrastructural tissue analysis of extraocular muscle (EOM) obtained from a patient with seronegative myasthenia gravis (MG) with treatment-resistant ophthalmoplegia for 3.5 years. The EOM demonstrated predominantly myopathic features and ultrastructural evidence of mitochondrial dysfunction, but the most striking features were increased endomysial collagen and adipocyte replacement of muscle fibers.

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Article Synopsis
  • Exfoliation syndrome (XFS) is a significant risk factor for secondary glaucoma, contributing to blindness globally, with known genetic variants in LOXL1 and CACNA1A linked to the condition.
  • Researchers conducted a study analyzing samples from multiple countries, discovering a rare protective allele at LOXL1 and refining its association, which had been previously inconsistent across different populations.
  • A genome-wide association study identified seven significant genetic loci related to XFS, providing new insights into its biological mechanisms and emphasizing the role of rare LOXL1 variants in the disease's development.
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Although extraocular muscles are commonly affected by myasthenia gravis (MG) at presentation, a treatment-resistant ophthalmoplegic complication of MG (OP-MG) occurs in younger patients with African-genetic ancestry. In MG, pathogenic antibodies activate complement-mediated muscle damage and this may be potentiated in some OP-MG cases because of relative deficiency of decay-accelerating factor/CD55. Extending this argument, we hypothesized that OP-MG individuals may harbor African-specific polymorphisms in key genes influencing extraocular muscle remodeling.

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Exfoliation syndrome (XFS) is a common, age-related, systemic fibrillinopathy. It greatly increases risk of exfoliation glaucoma (XFG), a major worldwide cause of irreversible blindness. Coding variants in the lysyl oxidase-like 1 (LOXL1) gene are strongly associated with XFS in all studied populations, but a functional role for these variants has not been established.

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Article Synopsis
  • Exfoliation syndrome (XFS) is a common cause of a type of eye disease called open-angle glaucoma.
  • Researchers studied the DNA of nearly 1,500 people with XFS and compared it to over 1,100 healthy people from Japan, and then looked at even more data from around the world.
  • They found a new gene that seems to increase the chances of getting XFS and confirmed another gene that behaves differently in people from different backgrounds.
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Purpose: To investigate whether DNA copy number variants (CNVs) in the lysyl oxidase-like 1 (LOXL1) gene are associated with exfoliation glaucoma (XFG) in black South Africans.

Methods: Black South African subjects with XFG and age-matched unaffected controls were recruited from the St. John Eye Hospital in Soweto (Johannesburg, South Africa) and East London Hospital Complex (Eastern Cape, South Africa) using standard clinical examination techniques.

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Purpose: Myocilin (MYOC) mutations are associated with primary open-angle glaucoma (POAG) in multiple populations. Here we examined the role of MYOC mutations in a black South African population with primary open-angle glaucoma (POAG).

Methods: Unrelated black South African subjects with POAG and unaffected controls were recruited from the St.

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Objective: To investigate the association between 2 lysyl oxidase-like 1 (LOXL1) polymorphisms, rs1048661 (R141L) and rs3825942 (G153D), and exfoliation syndrome (XFS) in black South African individuals.

Methods: A total of 43 black patients with XFS and 47 ethnically matched controls were recruited for genetic analysis. Samples were analyzed for presence of the LOXL1-R141L and G153D variants using restriction fragment length polymorphism analysis.

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