Fragile X syndrome: The role of molecular diagnosis and screening in an integrated approach to services
08-01-2002 | Dépistage et pratiques cliniques préventives
In 1996, the Conseil d’évaluation des technologies de la santé (CETS) started a project on the problems posed by the transfer of knowledge from medical genetics research to new clinical applications. The Agence d’évaluation des technologies et des modes d’intervention en santé, as CETS was renamed, with the support of a multidisciplinary committee, is thus examining technologies derived from molecular biology, which is making available an increased number of diagnostic and prenatal tests for many diseases.
CETS chose four diseases as a priority, namely, Duchenne and Becker muscular dystrophies, myotonic dystrophy, tyrosinemia and fragile X syndrome, its criteria being the seriousness and incidence of the disease, test availability and reliability, and the availability of preventive measures. The fourth and present report in this series concerns fragile X syndrome, the leading cause of mental retardation, after Down’s syndrome. Its prevalence is at least 1 per 4.000 males and 1 per 8.000 females. Early clinical diagnosis of this disease is difficult.
This assessment summarizes the state of knowledge regarding the genotypic analysis of individual with the syndrome and screening for asymptomatic carriers of a dynamic mutation on the FMR1 (fragile X mental retardation 1) gene. This report also discusses the usefulness of developing or maintaining such a service in Québec’s health-care system and the management of affected individuals by medical, social and educational services, and explore the ethical issues involved.
In conclusion, the Agency believe that the conditions are in place for one or two laboratories meeting the necessary standards of quality to perform diagnostic tests for fragile X syndrome. Other implications regarding the clinical support and follow-up to be provided to the families concerned, the necessary medical, social and educational resources, research, and the organizational aspect of the services are discussed as well.