Family Communication and Cascade Testing for Fragile X Syndrome.

A total of 679 families who had at least one child with fragile X syndrome (FXS) were recruited from a research registry to participate in a survey examining cascade testing and communication about FXS. Families had a total of 1117 children (804 males, 313 females). Most families (84 %) had tested all of their children. The main reason for not testing, which did not differ by gender or age of the child, was that the child did not show signs of FXS (68 %). Families talked with their children about FXS occasionally (47 %) although 16 % said they do not talk about it. Most families (66 %) had told their children their FXS status, with males and those with the premutation being less likely to be told test results. Of those that did not, 46 % said that they would tell their child when they were old enough to understand, whereas 34 % had either decided they would not tell or were not sure if or when they were going to tell. About a quarter of respondents (28 %) indicated that no extended family members had been tested, with income and communication about FXS being the strongest predictors. Results from this large scale survey provide important data on how families communicate about FXS and reasons testing is or is not sought. This information can be used by genetic counsellors in providing follow-up to families after a FXS diagnosis.