Frederick Sanger, the British biochemist who twice won the Nobel Prize, has died at the age of 95.
Fellow researchers have described him as "one of the greatest scientists of any generation" and as "a real hero" of British science.
He is considered the "father of genomics" after pioneering methods to work out the exact sequence of the building blocks of DNA.
Dr Sanger also developed techniques to determine the structure of proteins.
He was born in 1918 in Gloucestershire and initially planned to follow his father into medicine.