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EPHA2 polymorphisms and age-related cataract in India
Periasamy Sundaresan1, Ravilla D Ravindran, Praveen Vashist
1Department of Genetics, Dr. G. Venkataswamy Eye Research Institute, Aravind Medical Research Foundation, Aravind Eye Hospital, Madurai, Tamil Nadu, India.
Plos One
|March 14, 2012
Summary
Genetic variants in EPHA2 are associated with cortical and posterior sub-capsular (PSC) cataracts in the Indian population. These findings align with European studies for cortical cataracts and present new evidence for PSC cataracts, which are common in India.
Area of Science:
- Genetics
- Ophthalmology
- Population Health
Background:
- Cataract is a leading cause of blindness globally, with significant variations in prevalence and type across different populations.
- Single nucleotide polymorphisms (SNPs) in the EPHA2 gene have been previously associated with cataract in European cohorts.
- Understanding the genetic underpinnings of cataract in diverse populations like India is crucial for targeted prevention and treatment strategies.
Purpose of the Study:
- To investigate whether EPHA2 gene single nucleotide polymorphisms (SNPs) previously identified in European populations are associated with cataract in an Indian population.
- To determine the association of specific EPHA2 SNPs (rs3754334, rs7543472, and rs11260867) with different types of cataract, including nuclear, cortical, and posterior sub-capsular (PSC).
Main Methods:
- A population-based genetic association study was conducted in randomly sampled villages across north and south India.
- Participants aged 40 and over underwent clinical examination, lens photography graded using Lens Opacification Classification System (LOCS III), and provided blood samples for genotyping.
- Logistic regression was used to analyze the association between EPHA2 SNPs and cataract, adjusting for age, sex, and location.
Main Results:
- No association was found between the EPHA2 SNP rs3754334 and any type of cataract.
- Minor allele homozygous genotypes of rs7543472 and rs11260867 were significantly associated with an increased risk of cortical cataract.
- These two SNPs also showed a trend towards association with posterior sub-capsular (PSC) cataract, with rs7543472 reaching statistical significance.
Conclusions:
- The findings confirm the association of EPHA2 variants with cortical cataracts in an Indian population, consistent with previous European studies.
- New evidence suggests an association between specific EPHA2 SNPs and PSC cataracts, a type particularly prevalent in the Indian subcontinent.
- These results highlight the importance of population-specific genetic investigations for understanding cataract etiology.
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