Professor John Edwards

Geneticist whose work on chromosome defects included the identification of Edwards syndrome

John Hilton Edwards, geneticist: born London 26 March 1928; Ship's Surgeon, Falkland Islands Dependency Survey 1952-53; Lecturer, Department of Social Medicine, Birmingham University 1956-58, 1961-65, Senior Lecturer 1965-66, Reader in Human Genetics 1966-69, Professor of Human Genetics 1969-79; Member, MRC Unit on Population Genetics, Oxford 1958-60; Geneticist, Children's Hospital of Philadelphia 1960-61; Visiting Professor of Paediatrics, Cornell University and Senior Investigator, New York Blood Center 1967-68; FRS 1979; Professor of Human Genetics, Oxford University 1979-95 (Emeritus); Professorial Fellow, Ke ble College, Oxford 1979-95; married 1953 Felicity Toussaint (two sons, two daughters); died Oxford 11 October 2007.

Edwards syndrome is, after Down's syndrome, the most common disease caused by having an extra chromosome. Its discovery was one of many advances made by John Edwards, Emeritus Professor of Genetics at Oxford University.

Others included suggesting that placental sampling, introduced to detect Rhesus-negative babies, should also be used to detect chromosome abnormalities such as Down's syndrome. This is now a routine procedure. He contributed to our knowledge of the inherited form of hydrocephalus, and also reported a series of 20 cases of a rare genetic disease, Cornelia de Lange syndrome. He developed a widely-used research tool called the "Oxford grid" to map and compare gene sequences in different animal species, including humans.

Edwards was the son of a London surgeon. He didn't learn to read until he was nine, in part because he was rarely read to, which he later said gave him time to think. From Uppingham School, he went to Trinity Hall, Cambridge to study medicine, doing his clinical training at the Middlesex Hospital in London. While at the Middlesex he married Felicity Toussaint, a fellow medical student from Oxford.

He then did his National Service in the Artists' Rifles, part of the territorial SAS, where he learned to parachute. He described parachuting from a balloon as the most frightening experience of his life. He followed this with nine months as ship's doctor – doubling as dentist – on a scientific research ship, the John Biscoe, voyaging round the South Atlantic and Antarctic. On his return he was found to have tuberculosis at the top of one lung, for which he was prescribed bed-rest. He passed the time by teaching himself statistical methodology.

After his recovery, he spent three years in junior medical jobs in general medicine, neurology, pathology and psychiatry, at hospitals in London and Hampshire. In 1956 he joined Birmingham University, where he spent 27 years. He started as Lecturer in the Department of Social Medicine in the Institute of Child Health, and rose to be Professor of Human Genetics, heading a new department of clinical genetics. It was during his first year there, when placental sampling had been introduced nationally, that he suggested via The Lancet that it could be used to detect genetic abnormalities.

During his time at Birmingham, he spent 1958-60 at the Population Genetics Unit of Oxford University, returning to Birmingham regularly, where he recognised the defects caused by having an extra chromosome 18. He reported these in The Lancet and the syndrome was later named after him.

He spent a sabbatical (1960-61) at the Philadelphia Children's Hospital, and 1966-67 at the New York Blood Center and Cornell Medical Center. During his time at Philadelphia he attended a now-famous genetics course at Bar Harbor in Maine, organised and presented by Professor Victor McKusick of Baltimore. They became friends, and in later years Edwards taught in the course. In 1979, his last year at Birmingham, he was elected to fellowship of the Royal Society.

As Professor of Genetics at Oxford from 1979, his main work was in the development of the "Oxford grid", a chart for mapping and comparing gene sequences in different species of animals; he found comparable linked strings of genes in a range of animals, a concept called "syngeny". In Sydney, where Edwards did collaborative work, there is an "Oxgrid project".

He made many other contributions: he played a major role in human gene-mapping workshops held between 1973 and 1991; directed the West Midlands Human Cytogenetics Laboratory for four years; and was Visiting Professor at Newfoundland University. He was a genetics consultant to the World Health Organisation from 1972, and a consultant genetics investigator in Iceland, which is extensively studied for its compact gene pool. This meant several visits to Iceland, on one occasion overlapping with the Fischer-Spassky chess matches and meeting Boris Spassky. His interests in restricted gene pools also extended to Labrador, Newfoundland, pigs in Australia and sheep in New Zealand.

At the Social Medicine Department at Birmingham, John Edwards had been mentored by Lancelot Hogben, author of Mathematics for the Million, one of the most successful science books ever written. John Edwards's brother Anthony had a parallel career as a statistical geneticist at Cambridge, originally working under the statistician R.A. Fisher. The two brothers were nicknamed "Hogben's Edwards" and "Fisher's Edwards".

Edwards, slender and boffin-like, was loved and respected for his support for his junior workers, his good nature and his altruism. Sir Walter Bodmer, who preceded him as professor at Oxford, said, "He had a fine feel for the subject of human genetics, including a historical perspective, and always an original way of looking at problems and presenting them." Sir David Weatherall, Regius Professor of Medicine at Oxford, said Edwards was "one of the nicest and cleverest of our field". And Professor Victor McKusick, of Johns Hopkins, said, "John was of quick wit in both senses of the word. His humour was rarely if ever malicious or unkind. Among his colleagues his absentmindedness was legendary, and it enhanced rather than detracted from the respect in which his colleagues held him."

Edwards read widely, with a particular fondness for Martin Gardner, Edward Gibbon and G.K. Chesterton. He had a recreational interest in mathematics, and went walking, skiing and gliding. He was energetic, happily chopping trees into logs. When his children were young, he would take them to the cinema and work out mathematical formulae on the backs of punch-cards in the near-darkness. He did his own computer programming throughout his career.

In his retirement he took an interest in leprosy and collaborated with the head of the Indian medical research council. He was diagnosed with prostate cancer in 2000 but remained active until July last year.

Caroline Richmond