The Indian Journal of Pediatrics

, Volume 76, Issue 5, pp 513–517 | Cite as

Genotype/phenotype association in Indian congenital aniridia

  • Guruswamy Neethirajan
  • Abraham Solomon
  • Subbaiah Ramasamy Krishnadas
  • Perumalsamy Vijayalakshmi
  • Periasamy Sundaresan
Special Article


The developmental birth eye disorder of iris is known as aniridia. Heterozygous PAX6 gene, which causes human aniridia and small eye in mice, is located on chromosome 11p13. The variability had been documented between the affected individuals within the families, is due to genotypic variation. Haploinsufficiency renders PAX6 allele non-functional or amorphic, however it presents hypomorphic or neomorphic alleles. India is not a well-studied ethnic group, hence the focus on congenital aniridia gene analysis supports the literature and the phenotypic association were analysed both in sporadic as well as familial. The consistent association of truncating PAX6 mutations with the phenotype is owing to non-sense-mediated decay (NMD). It is presumed that the genetic impact of increased homozygosity and heterozygocity in Indian counter part arises as the consequence of consanguineous marriages. The real fact involved in congenital aniridia with other related phenotypes with PAX6 mutations are still controversial.

Key Words

Aniridia PAX6 Amorphic Hypomorphic Marfan’s syndrome Ectopia lentis Sclerocornea 


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Copyright information

© Dr. K C Chaudhuri Foundation 2009

Authors and Affiliations

  • Guruswamy Neethirajan
    • 1
    • 4
    • 5
  • Abraham Solomon
    • 1
  • Subbaiah Ramasamy Krishnadas
    • 2
  • Perumalsamy Vijayalakshmi
    • 3
  • Periasamy Sundaresan
    • 4
  1. 1.Department of OphthalmologyHebrew University Medical Center JerusalemJerusalemIsrael
  2. 2.Department of GlaucomaAravind Eye HospitalMaduraiIndia
  3. 3.Department of Pediatric Ophthalmology and StrabismusAravind Eye HospitalMaduraiIndia
  4. 4.Department of GeneticsAravind Medical Research FoundationMaduraiIndia
  5. 5.Department of BiotechnologyAlagappa, UniversityTamilnaduIndia
  6. 6.Department of OphthalmologyHebrew University Medical CenterMaduraiIndia

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