The Human Genome Project (HGP) was a 13-year-long project coordinated by the USA and involving groups from other nations. The project goals included identifying all the genes in the human DNA and determining the three billion base pairs that make up human DNA. In the UK, clinical genetic services are based in regional centres providing services for populations of between two to six million. These centres include molecular genetics, cytogenetic and biochemical genetic laboratories. In parallel with the improved understanding of human molecular science, a new field of public health has been established to investigate and implement the fruits of the scientific endeavour in order to improve the health of the population. This field is called public health genetics or public health genomics. The development of new genetic tests has been an early application of the improved understanding of human genomics.