Evaluation of the norrie disease gene in a family with incontinentia pigmenti.

Incontinentia pigmenti (IP) is an ectodermal multisystem disorder which can affect dental, ocular, cardiac and neurologic structures. The ocular changes of IP can have a very similar appearance to the retinal detachment of X-linked familial exudative vitreoretinopathy, which has been shown to be caused by the mutations in the Norrie disease gene. Therefore, it is of interest to determine whether similar mutations in the gene can account for the retinal pathology in patients with IP. To test our hypothesis, we have analyzed the entire Norrie disease gene for a family with IP, by single strand conformational polymorphism followed by DNA sequencing. The sequencing data revealed no disease-specific sequence alterations. These data suggest that ocular findings of IP are perhaps associated with different genes and there is no direct relationship between the genotype and phenotype.