[A large-scale diagnostic program for the fragile X-syndrome among the mentally retarded. II. Implications for parents and family].

OBJECTIVE: Studying the attitudes and reactions of (non)consenting parents/guardians of mentally retarded patients regarding the screening programme for the fragile X syndrome in the Netherlands. DESIGN: Observative-descriptive. SETTING: Department of Clinical Genetics, University Hospital Dijkzigt and Erasmus University, Rotterdam, the Netherlands. METHOD: Since 1992 a screening program for the fragile X syndrome has been conducted in 5 institutions giving residential care (1869 individuals) and 16 special schools (1483 children) in the southwestern Netherlands. Patients with an unknown cause for their mental handicap were, after the parents/guardians' written consent, briefly examined physically and a blood sample for DNA analysis of the FMRI gene was taken. The attitude and reactions of (non)consenting parents/guardians were assessed by pre- and post-test questionnaires. Of the 1531 persons who consented, 1090 were sent a letter before the test (response: 860; 79%) and 1030 after the test results (response: 681; 66%); of the 435 parents/guardians who had not consented, 153 (35%) responded. RESULTS: Seventy percent (1531/2189) of the parents/guardians consented to testing. Major motives to participate in the screening were the wish to obtain a diagnosis (82%), the hereditary implications (80%), and the support of research into mental retardation (81%). The majority of consenting parents/guardians (84%) as well as of non-consenting parents/guardians (78%) discussed the DNA test with other relatives. Major reasons for non-consenting were the blood test which was considered too stressful for their relative (61%) and the opinion that a 'definite' cause of the mental handicap in their relative was already known (44%). These parents/guardians were not opposed to genetic testing in general (72%). Of the consenting parents/guardians 34% would actively seek further investigations after exclusion of the fragile X syndrome in their relative. CONCLUSION: The fragile X screening programme was rated positively by parents/guardians.