Dr Daniel Brown

Dr Daniel Brown, who has died aged 89, was one of the leading UK organic chemists of the 20th century. His research was instrumental in helping his Cambridge University colleagues James Watson and Francis Crick uncover the double helix, the molecular structure of DNA, the substance which carries genes from generation to generation.

Arguably the chemistry discovery of all time, it won Watson, Crick and their fellow researcher Maurice Wilkins the Nobel Prize for Medicine in 1962. Dr Brown never claimed credit for his role but he always felt that another researcher, Rosalind Franklin, who had died by the time the prize was awarded, should have shared it with Crick, Watson and Wilkins, albeit posthumously.

Being a Glaswegian, he was a quiet man, unless riled. At Cambridge, he knew Watson and Crick were picking his brains during their in-between-research lunches at Cambridge's famous Eagle pub. When Crick stormed into the Eagle on February 28, 1953, and famously announced: "We have found the secret of life," he was happy for them. Not so much for them, more for what the discovery of the double helix could do for mankind, for the understanding and treatment of usually fatal diseases.

Through most of his career, Dan Brown, as he was always known, focussed on mutagenics (genetic mutation) and RNA (ribonucleic acid, the single strand version of DNA, or deoxyribose nucleic acid). His research into mutagenics was crucial in bridging a scientific divide; how we evolve in massive leaps (for example, from apes to humans, and yet pass on our genes a generation at a time).

His research into RNA was a major factor in guiding Watson and Crick into their DNA breakthrough. His role was little known, except among fellow researchers, but his work on mutagenics gave doctors a clearer understanding of relatively modern diseases such as Aids or Ebola and helped give them methods of treating them.

"I had, by that time, generally got the RNA structure right and how it hydrolyses (breaks down) and therefore how enzymes hydrolyse; also the general chemical structure of DNA which is basis of the double helical structure described by Crick and Watson," he wrote many years ago.

Daniel McGillivray Brown was born in the Glasgow suburb of Giffnock in 1923, where he went to Giffnock Primary School, then on to Glasgow Academy and eventually to Glasgow University, his studies (1940-45) coinciding almost exactly with the war years.

His father, also Daniel, owned one of Glasgow's most famous restaurants, widely known as Danny Brown's, on St Vincent Street.

After his father tired of the hospitality business he decided to be a farmer, near Dunblane.

The young Dan was a somewhat bored, 18-year-old member of the Home Guard in 1941, waiting to be called up to join the rest of his family at war. But then a small plane landed near Giffnock. It was his night off, but he had the pleasure of working on his German the next morning with the pilot of the plane – Rudolf Hess, Hitler's deputy, who felt he might end the war by landing in Scotland on a peace mission.

At Glasgow University, although studying chemistry, he realised that, although one is forced into compartments at that age, compartments merge. While slaving over a Bunsen burner by day, he read Sartre, Mauriac, Gide or Duhamel in between snakebites (shandies with a purpose) at the university union.

In his retirement years, Dr Brown continued to read and be enamoured by art. He was an expert on, and exporter of, Scottish literature, particularly of the "renaissance" of the first half of the 20th century. He was honoured as a fellow of King's College, Cambridge, and of the Royal Society.

Dr Dan Brown died at his home in Cambridge. He is survived by his wife of almost 50 years, Margaret (née Herbert), daughters Catherine, Frances and Moira, grandchildren Syrita, Sean, Joe and Danny, and great grand-daughter Iona.