Abstract
We assessed the present status of chromosome and gene analyses utilized in Japan for the diagnosis of fragile X syndrome. Nursery facilities for the mentally handicapped and hospitals completed a mail-in-questionnaire including information on the number of patients diagnosed with the syndrome, the types of diagnostic analyses used, and the need for such analyses. Among 517 responders, ninety-five (18.4%, more frequently in hospitals) reportedly conducted chromosome or gene analyses, which established the diagnosis of fragile X syndrome in 56 patients, accounting for 2.2% of patients who underwent the analyses, and 0.13% of the patients included in this study. Each responder's experience with chromosome or gene analyses were related to his/her demand for them. Some facilities that had not utilized these analyses requested information on them as well as access to them. A larger number of specialists interested in diagnostic screening are essential to establish a diagnosis system of fragile X syndrome.