Delivering genetic screening to the community.

Concern is often expressed that, in the future, screening for genetic risk will become too widespread. Haemoglobin disorders (the thalassaemias and sickle cell disorders) offer an excellent model for genetic screening, because they are common and severe. They are recessively inherited. Carriers can be detected by conventional blood tests with an accuracy of 99%, so couples at risk can be identified before they have children and offered genetic counselling and prenatal diagnosis. Carrier-screening programmes have been in place in several countries for over 20 years and now offer extensive practical experience of the problems of delivering the service equitably to entire populations. This experience suggests that the main risk is of too little rather than too much genetic screening, and of doing it badly, and demonstrates the need for a discipline of 'community genetics'. Here I propose that modern information technology has a central role in providing communities with adequate access to correct genetic information.