Prenatal diagnosis of the common haemoglobin disorders.

New techniques of DNA analysis have been applied to the prenatal diagnosis of the common haemoglobin disorders. Currently, it is possible to provide a comprehensive programme for the prevention of these conditions, although this entails the use of several different techniques including globin chain synthesis analysis, direct identification of mutations with restriction enzymes, linkage analysis of restriction fragment length polymorphisms, and the use of oligonucleotide probes. At present, the best combination of these approaches has to be worked out for individual populations, but as the techniques of chorion villus sampling and DNA analysis improve it should be possible to rationalise these prenatal diagnosis programmes and thus make them simpler and less expensive.