Lionel Penrose

Lionel Sharples Penrose, FRS (11 June 1898 – 12 May 1972) was a British psychiatrist, medical geneticist, mathematician and chess theorist, who carried out pioneering work on the genetics of mental retardation.

Education

Penrose was educated at the Downs School, Colwall and the Quaker Leighton Park School, Reading. On leaving school in 1916, he served, as a conscientious objector, with the Friends' Ambulance Unit/British Red Cross in France until the end of the First World War. He went on to study at St. John's College, Cambridge; he was a Cambridge Apostle.

Career

Penrose's "Colchester Survey" of 1938 was the earliest serious attempt to study the genetics of mental retardation. He found that the relatives of patients with severe mental retardation were usually unaffected but some of them were affected with similar severity to the original patient, whereas the relatives of patients with mild mental retardation tended mostly to have mild or borderline disability. Penrose went on to identify and study many of the genetic and chromosomal causes of mental retardation (then called mental deficiency). This body of work culminated in the book, The Biology of Mental Defect (Sidgwick and Jackson, Ltd., London, U.K., 1949).