"Scientist whose unsung role was crucial in the deciphering of DNA” The Guardian
Born 27th June 1919 – Died 5th February 2003
Alexander Stokes was the first scientist to work out that the DNA (deoxyribonucleic acid) molecule was probably helical in shape.
Stokes, a crystallographer, was one of the team of scientists at King's College, London, involved in examining evidence of the structure of DNA from X-ray diffraction patterns. He was born at Macclesfield on June 27 1919, and educated at Cheadle Hulme School, Manchester, and at Trinity College, Cambridge, from which he graduated with a First in Natural Sciences. He then became a demonstrator in electricity at the university and worked in the Cavendish Laboratories as a research student in the field of X-ray crystallography.
In 1945 he became a lecturer in Physics at the Royal Holloway College and, two years later, was recruited to King's College by John Randall to strengthen the research group studying the molecular structure of biological molecules. He became a senior lecturer there in 1961. During the 1950s and 1960s Stokes worked on the structure of large biological molecules, and on the study of light scattering by suspensions of randomly orientated long prisms and X-ray scattering of chain molecules. He was a long-term member of the College Board of Studies in Physics, and was its chairman for a number of years. He retired in 1982. He has been credited as being the first person to demonstrate that the DNA molecule was probably helical in shape.