Negative-configuration electroretinogram in Oregon eye disease. Consistent phenotype in Xp21 deletion syndrome.
OBJECTIVE: To determine whether abnormal configurations on electroretinogram were a consistent finding in patients with Xp21 deletion and to characterize the associated ophthalmologic phenotype. DESIGN: Case series. SETTING: University hospitals and eye institutes. PATIENTS: Five patients with complex glycerol kinase deficiency (Duchenne-type or Becker's muscular dystrophy, glycerol kinase deficiency, and congenital adrenal hypoplasia) and demonstrated chromosomal deletions at Xp21. Control patients were matched by age. MAIN OUTCOME MEASURES: Clinical information was obtained from medical records. Complete ophthalmologic examinations were performed. Electroretinography was performed using a Ganzfeld technique and chloral hydrate sedation. RESULTS: We report the clinical features and abnormal configurations on electroretinograms of five patients with complex glycerol kinase deficiency, including follow-up studies on a previously described patient. The original patient had ocular hypopigmentation; four, strabismus; two, myopia; three, astigmatism; and one, symptomatic night blindness. All had negative configurations on scotopic electroretinograms showing a reduced-amplitude B wave in the dark-adapted state. CONCLUSIONS: Our original report suggested a diagnosis of Aland Island eye disease, which appears to be an incomplete form of congenital stationary night blindness. Linkage data place Aland Island eye disease and congenital stationary night blindness at Xp11, whereas our patients had deletions at Xp21. The phenotype reported here may represent the effects of a single gene defect or the compound effects of the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency). The phenotype is referred to as Oregon eye disease.