The resource implications and service outcomes of genetic services in the context of DNA technology.

The use of DNA technology has transformed genetic counselling services for single gene disorders. For conditions such as Duchenne muscular dystrophy and cystic fibrosis, both of which cause severe morbidity and premature death, DNA tests mean that individuals can be told with greater certainty whether they are carriers of a genetic trait and of the likelihood of their having a child affected by the disorder. This paper presents the findings of an evaluation of the resource implications and service outcomes of genetic services in the context of DNA technology (DNA services). Results are based on data collected over a 4-year period from three large genetics centres throughout the United Kingdom. Our conclusions are that for the conditions for which they are commonly used, and as a regionally based service, DNA services are effective and relatively inexpensive. For severe conditions, and for neurological disorders, although tests will not alter family size plans the demand for tests during pregnancy will be high and the results will have a significant impact on individuals' decisions regarding the continuation of their pregnancies. For conditions of variable severity, those that start late in life or are amenable to treatment, the demand for tests is likely to be low. In comparison with the general population we found a greater existence of psychological side effects amongst counsellees. These effects were linked to individuals having a close relative, usually a child, already affected by a disorder rather than being a consequence of the genetic counselling process.