The molecular diagnosis of hereditary and somatic disorders is a rapidly expanding field in modern medicine. Mutations in more than 1500 genes have been found to be associated with human diseases, and this figure is likely to rise significantly over the next few years as the genetic basis of more conditions becomes known. DNA sequencing is still probably the most widely used and reliable method of detecting gene mutations and sequence variations. However, it is expensive and time-consuming, and, increasingly, other methods are employed to screen DNA fragments for sequence variations. For a screening method to be useful, it must be fast, inexpensive and applicable to most genes. Ideally, it needs to provide information about the nature and position of a mutation and to minimize exposure of laboratory staff to hazardous reagents. Many of the protocols currently used fit some of these criteria, but there are few, if any, that fulfill all.
