The beginning of the new millennium was marked by the announcement that the vast majority of the human genome had been sequenced. This milestone in the exploration of the human genome was preceded by numerous conceptual and technological advances. They include, among others, the elucidation of the DNA double-helix structure, the discovery of restriction enzymes and the polymerase chain reaction (PCR), the development and automatization of DNA sequencing, and the generation of genetic and physical maps by the Human Genome Project (HGP). The consequences of this wealth of knowledge for the practice of medicine are profound. To date, the most.
