PREPARING FOR PRESYMPTOMATIC DNA TESTING FOR EARLY-ONSET ALZHEIMERS DISEASE CEREBRAL HEMORRHAGE AND HEREDITARY PICK DISEASE/

The acceptability of presymptomatic testing in 21 people at 50% risk f or the APP-692 mutation causing presenile Alzheimer's disease or cereb ral haemorrhage resulting from cerebral amyloid angiopathy (FAD-CH), a nd in 43 people at 50% risk for hereditary kick disease (HPD) was asse ssed. Neither group differed in demographic variables. Thirty-nine peo ple (64%) in the whole group would request presymptomatic testing if i t were clinically available, although two-thirds did not yet feel read y to take it. The most important reasons in the HPD and FAD-CH group f or taking the test were: to further basic research (42% and 47%, respe ctively), informing children (47% and 50%, respectively), future plann ing (29% and 47%, respectively), and relieving uncertainty (46% and 27 %, respectively). The most commonly cited effect of an unfavourable te st result concerned increasing problems for spouses (75% and 76%, resp ectively) and children (61% and 57%, respectively). Most respondents d enied that an unfavourable result would have adverse effects on person al mood or relationship. One-third of all respondents favoured prenata l testing where one of the parents had an increased risk for HPD or FA D-CH. Participants would encourage their offspring to have the test be fore starting a relationship (35%) and before family planning (44%). T hirty-seven percent of the respondents would encourage their children to opt for prenatal diagnosis. People at risk for HPD were significant ly more preoccupied with the occurrence of potential symptoms in thems elves, compared with those at risk for FAD-CH, reflecting the devastat ing impact that disinhibition in the affected patient has on the famil y. Our findings underline the need for adequate counselling and the av ailability of professional and community resources to deal with the im pact of test results in subjects and their relatives.