ABSTRACT
The identification in 1993 of a trinucleotide repeat mutation as the cause of Huntington’s Disease (HD) has greatly simplified predictive testing and eliminated many of the problems. Some people have even requested anonymous predictive testing in order to reduce the risk of discrimination for themselves and their families, but such arrangements inevitably interfere with the establishment of satisfactory follow-up arrangements and case reports. The list of other trinucleotide repeat disorders includes myotonic dystrophy, several different types of spinocerebellar ataxia, and a number of rare disorders such as DRPLA. The psychosocial issues raised by predictive testing for the other late-onset trinucleotide repeat disorders are essentially the same as for HD. Most of the provisions of the HD predictive test guidelines are equally relevant to these other disorders, and their use should prevent major problems and ensure high standards of clinical practice.
