Altered expression of genes in experimentally induced myopic chick eyes

Purpose: To identify a casual pathway between the alteration in visual expe rience, due to form deprivation and hyperopic defocus, and the increase in eye growth, we searched for candidate genes having regulatory effects on ey e growth under myopic conditions. Methods: The expression of the brain-derived neurotrophic factor, neurotrop hin-3, sonic hedgehog, nerve growth factor, Six-3 and the Lh-2 group of gen es in the transcriptional level after experimentally induced myopia (form-d eprivation by goggles and by hyperopic defocus using negative spectacle len ses) were evaluated by semiquantitative reverse transcriptional polymerase chain reaction and Northern blot analysis. Results: Results showed that only the sonic hedgehog gene was differentiall y expressed in the experimentally induced myopic retinal samples compared w ith controls. Conclusions: The sonic hedgehog gene may have regulatory functions in the s ignaling of the cascade of events that leads to axial elongation and vitreo us enlargement of the eye under myopic conditions. (C) 2001 Japanese Ophtha lmological Society.