Born: August 13, 1918 Died: November 19, 2005

Frederick Sanger, who has died aged 95, was a biochemist who twice won the Nobel Prize in chemistry and was a pioneer of genome sequencing. He was one of just four individuals to have been awarded two Nobel Prizes; the others were Marie Curie, Linus Pauling and John Bardeen.

He first won the Prize in 1958 at the age of 40 for his work on the structure of proteins. He had determined the sequence of the amino acids in insulin and showed how they are linked together. He later turned his attention to the sequencing of nucleic acids and develop techniques to determine the exact sequence of the building blocks in DNA. That led to his second Nobel Prize, awarded jointly in 1980 with Stanford University's Paul Berg and Harvard University's Walter Gilbert, for their work determining base sequences in nucleic acids.

He was born in Gloucestershire and initially planned to study medicine like his father. However, he switched fields and earned a degree in natural sciences from Cambridge University in 1939.

During the Second World War, as a Quaker he registered as a conscientious objector and worked on completing his PhD on protein metabolism. He then joined a research group to work on proteins and chose to study insulin because of its medical implications. He perfected a way of unravelling the complete amino acid sequence of even the most complex of proteins.

In the 1960s, he became a senior member at the Medical Research Council's new laboratory for molecular biology at Cambridge. Venki Ramakrishnan, deputy director of the MRC Laboratory, said it would be impossible to overestimate the impact Sanger had on modern genetics and molecular biology.

In addition to the Nobel Prizes, Sanger was made a fellow of the Royal Society in 1954, Commander of the Order of the British Empire in 1963 and the Order of Merit in 1986. He declined a knighthood saying he preferred not to be called sir.

According to The Sanger Institute, which was opened in 1993 and continues his work in DNA sequencing, when he was asked if he would mind an institute being named after him, Sanger agreed but said: "It had better be good."

The MRC Laboratory of Molecular Biology - which Sanger helped found in 1962 - praised him as a modest and self-effacing man whose contributions made an extraordinary impact on molecular biology. Jeremy Farrar, director of the Wellcome Trust, called Sanger the father of the genomic era.

Sanger retired in 1983. He is survived by three children - Robin, Peter and Sally.