Purpose: Few studies have investigated the eye and vision dysfunctions of children with the fragile X syndrome.
Case report: We report on a preschool boy with bilateral macular dysplasia and fragile X syndrome. His ocular features and phenotypic and genetic expressions are described. His mentally normal mother was identified as an expansion mutation carrier, and his older sister has learning disabilities, astigmatic refractive error, squint, and mild ptosis. Intrauterine infection has been excluded.
Conclusion: To our knowledge, the association of macular dysplasia with fragile X syndrome has not been reported. The finding of macular dysplasia might be a coincidental developmental disorder and not a part of the syndrome. It could be considered a condition causing visual deficit with nystagmus in fragile X syndrome.