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Updated: Aug 7, 2026
Three Different Protocols of Corneal Collagen Crosslinking in Keratoconus: Conventional, Accelerated and Iontophoresis
Published on: November 12, 2015
No VSX1 gene mutations associated with keratoconus
Anthony J Aldave1, Vivek S Yellore, Andrew K Salem
1Cornea Service, The Jules Stein Eye Institute, David Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA. aldave@jsei.ucla.edu
Purpose:
To determine whether mutations of the VSX1 gene play a pathogenetic role in the development of keratoconus (KTCN).
Methods:
DNA extraction, PCR amplification, and direct sequencing of the VSX1 gene were performed in 100 unrelated patients with diagnoses of clinical and topographic features of KTCN.
Results:
Of the four previously identified presumed pathogenic mutations in the VSX1 gene (Leu17Pro, Asp144Glu, Leu159Met, and Arg166Trp), only Asp144Glu was identified in a single affected patient. Two novel single nucleotide polymorphisms (SNPs), both resulting in synonymous substitutions, were identified: c.53G>T (Ser6Ser) in four affected patients and c.209G>T (Pro58Pro) in two affected patients. Two previously reported SNPs were also identified: c.426C>A (Arg131Ser) in one affected patient and c.581A>G (Ala182Ala) in 51 of the 100 affected patients.
Conclusions:
Only one of the presumed pathogenic mutations in the VSX1 gene, Asp144Glu, was identified in a single member of the cohort of affected patients. However, as previously demonstrated, Asp144Glu is a non-disease-causing polymorphism. The absence of pathogenic mutations in the VSX1 gene in a large number of unrelated KTCN patients indicates that other genetic factors are involved in the development of this disorder.
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