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Published on: November 12, 2015
Polymorphisms in COL4A3 and COL4A4 genes associated with keratoconus.
Mirna Stabuc-Silih1, Metka Ravnik-Glavac, Damjan Glavac
1Eye Hospital, University Medical Centre, Ljubljana, Slovenia.
Molecular Vision
|December 24, 2009
Summary
Genetic analysis of COL4A3 and COL4A4 genes in Slovenian keratoconus (KC) patients revealed no mutations but identified specific polymorphisms significantly associated with KC. These findings suggest a potential link between these gene variants and the development of KC.
Area of Science:
- Ophthalmology
- Genetics
- Molecular Biology
Background:
- Keratoconus (KC) is an eye condition potentially linked to alterations in collagen types I and III.
- Collagen type IV, alpha-3 (COL4A3) and collagen type IV, alpha-4 (COL4A4) genes are implicated in collagen production and may play a role in KC pathogenesis.
Purpose of the Study:
- To investigate the significance of alterations in the COL4A3 and COL4A4 genes in Slovenian patients diagnosed with keratoconus.
- To screen for polymorphisms within these genes and assess their association with KC.
Main Methods:
- The study involved 104 unrelated KC patients and 157 healthy controls from Slovenia.
- DNA was extracted, and COL4A3 and COL4A4 gene exons were amplified via PCR.
- Single-strand conformation analysis (SSCA) was employed for screening, followed by sequencing of detected migration shifts. Fisher's exact test was used for statistical analysis.
Main Results:
- Eight polymorphisms were identified in COL4A3 and six in COL4A4.
- Allele differences in D326Y (COL4A3) and M1237V, F1644F (COL4A4) were significantly distinctive in KC patients (p<0.05).
- Specific genotypes for P141L, D326Y, G895G (COL4A3) and P482S, M1327V, V1516V, F1644F (COL4A4) showed significant genotype distribution differences between KC patients and controls.
Conclusions:
- This study represents the first mutational screening of COL4A3 and COL4A4 genes in KC patients within a Slovenian population.
- No direct mutations in COL4A3 or COL4A4 were found to be related to KC; however, seven previously described polymorphisms showed significant associations with KC under various genetic models.
- The detected polymorphisms, combined with existing data on type IV collagen expression and chromosomal instabilities, suggest a potential role for these genetic variations in keratoconus development.
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