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Aniridia
Anophthalmia
Microphthalmia
Developmental Eye Disease

  • PAX6
  • SOX2
  • SIX6
  • OTX2
  • VSX2
Mutation analysis for five genes involved in development eye disease is offered.

PAX6
It has been estimated that over 80% of patients with aniridia without deletion of the PAX6 gene have a heterozygous mutation identifiable by DNA sequencing as performed by GeneDx. Most of the identified mutations are loss-of-function mutations, including nonsense and frame-shift mutations. Individuals with other developmental eye abnormalities may also have mutation in the PAX6 gene and homozygous PAX6 mutation has been associated with anophthalmia.

SIX6 and SOX2
The etiology of anophthalmia and microphthalmia is heterogeneous and includes chromosomal abnormalities, prenatal exposures, and single gene disorders. Syndromic anophthalmia is associated with mutation in the SOX2 gene. In one study, eleven percent of individuals with sporadic bilateral anophthalmia were found to have a truncating mutation in the SOX2 gene. Other associated findings were male genitourinary abnormalities, myopathy, and spastic diplegia. Heterozygous deletion of SIX6 has been seen in some cases of bilateral anophthalmia.

OTX2
Haploinsufficiency of OTX2 may be associated with anophthalmia and microphthalmia. OTX2 mutations have also been reported in association with brain malformations and pituitary insufficiency.

VSX2
VSX2 mutations are associated with isolated ocular finding without other systemic malformations.

GeneDx offers mutation analysis of the PAX6, SIX6, OTX2, VSX2 and SOX2 genes as separate tests. Using genomic DNA obtained from buccal (cheek) swabs or blood (1-5 ml in EDTA), bi-directional sequence analysis of the coding region is offered for PAX6, SOX2, OTX2 and VSX2 genes. This analysis is expected to identify most types of mutations with exception of gross deletions. When indicated, targeted array CGH analysis with exon-level resolution (ExonArrayDx) is available to evaluate for a deletion/duplication involving PAX6, SOX2, SIX6, OTX2 or VSX2. Mutation-specific testing and prenatal diagnosis is available once the mutation in a family has been defined.

Information Sheet (PAX6), including prices and CPT codes Back to the List
Information Sheet (SOX2, OTX2, VSX2, SIX6), including prices and CPT codes  
Consent Document  
Genetic Test Sample Submission Form (Test Requisition Form) including Payment Options  
Aniridia, Iris, Eye, Wilms, WAGR, PAX, SOX, SIX, Anophthalmia, Anopthalmia, Microphthalmia, Micropthalmia, Coloboma, Cataract, Optic nerve

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