Genetic Testing in Pediatric Ophthalmology

  • Ishwar Chander Verma
  • Preeti Paliwal
  • Kanika Singh
Review Article

Abstract

The authors review the utility of genetic testing in ophthalmic disorders – precise diagnosis, accurate prognosis, genetic counseling, prenatal diagnosis, and entry into gene-specific therapeutic trials. The prerequisites for a successful outcome of a genetic test are an accurate clinical diagnosis, a careful family history that guides which genes to study, and genetic counseling (both pre-test and post-test). The common eye disorders for which genetic testing is commonly requested are briefly discussed – anophthalmia, microphthalmia, coloboma, anterior segment dysgenesis, corneal dystrophies, cataracts, optic atrophy, congenital glaucoma, congenital amaurosis, retinitis pigmentosa, color blindness, juvenile retinoshisis, retinoblastoma etc. A protocol for genetic testing is presented. If specific mutations in a gene are common, they should form the first tier test, as the mutations in Leber hereditary optic neuropathy. If mutations in one gene are likely, sequencing of that gene should be carried out, e.g. GALT gene in galactosemia, RS1 gene in retinoshisis. Disorders with genetic heterogeneity require multi-gene panel tests, and if these show no abnormality, then deletion / duplication or microarray studies are recommended, followed in sequence by clinical exome (5000 to 6000 genes), full exome (about 20,000 genes or whole genome studies (includes all introns). It is fortunate that most genetic tests in ophthalmology are available in India, including gene panel and whole exome/genome sequencing tests.

Keywords

Achromatopsia Anophthalmia Anterior segment dysgenesis Coloboma Color blindness Congenital cataracts Congenital glaucoma Corneal dystrophies Exome sequencing Eye disorders Leber’s congenital amurosis LHON Multi-gene testing Optic atrophy Pedigree analysis Retinitis pigmentosa Retinoblastoma Retinoshisis Utility of genetic testing 

Notes

Compliance with Ethical Standards

Conflict of Interest

None.

Source of Funding

None.

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Copyright information

© Dr. K C Chaudhuri Foundation 2017

Authors and Affiliations

  • Ishwar Chander Verma
    • 1
  • Preeti Paliwal
    • 1
  • Kanika Singh
    • 1
  1. 1.Institute of Medical Genetics and GenomicsSir Ganga Ram HospitalNew DelhiIndia

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