Lionel Penrose

Lionel Penrose
Born	Lionel Sharples Penrose (1898-06-11)11 June 1898[1]
Died	12 May 1972(1972-05-12) (aged 73)
Alma mater	St. John's College, Cambridge
Known for	Penrose triangle Penrose method Penrose stairs[2] Penrose's Law[3][4] Penrose square root law Penrose–Banzhaf index
Awards	Fellow of the Royal Society[1] Lasker Award[5] James Spence Medal 1964.
Scientific career
Fields	Pediatrics, Psychiatry, Genetics
Institutions	University of Cambridge University College London

Lionel Sharples Penrose, FRS (11 June 1898 – 12 May 1972) was a British psychiatrist, medical geneticist, paediatrician, mathematician and chess theorist, who carried out pioneering work on the genetics of mental retardation.^[4][6] Penrose was the Galton professor of eugenics at University College London, and later emeritus professor.^[7]

Education

Penrose was educated at the Downs School, Colwall and the Quaker Leighton Park School, Reading, and later St John's College, Cambridge^[7] 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.^[7] At Cambridge he gained a first class degree in moral sciences before leaving for Vienna for a year, to study at the psychological department at the University of Vienna.^[7] In 1928 qualified with the conjoint in 1928 at St Thomas' Hospital before qualifying for a Doctor of Medicine in 1930.

Career

Penrose undertook research into schizophrenia, designing tests of intelligence that were non-verbal in nature, that are still in current use, and was one of the earliest researcher on the phenylketonuria condition in the 1930s.^[7]

Penrose's "Colchester Survey", produced as the report in 1938, in collaboration with the MRC called th MRC special report: No.229, Clinical and genetic study of 1,280 cases of mental defect^[7], 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, UK, 1949).

Penrose was a central figure in British medical genetics following World War II. From 1945 to 1965 he occupied the Galton Chair at the Galton Laboratory at University College London. He received a number of awards and honours including the 1960 Albert Lasker Award for Basic Medical Research.^[5] The Lasker citation read:

"Professor Penrose and his associates have been responsible over the years for studies which touch all aspects of human genetics, include genetic analyses of most of the known hereditary diseases, contributions to mathematical genetics, biochemical genetics, the study of gene linkage in man, and theoretical work on the mutagenic effect of ionizing radiations. Most recently their attention has been turned to abnormalities of human chromosomes associated with congenital defects, particularly mongolism (Down syndrome)."^[5]

Penrose's Law^[3][4] states that the population size of prisons and psychiatric hospitals are inversely related, although this is generally viewed as something of an oversimplification.^[8]

Penrose, a member of the Society of Friends (Quakers), was a lead figure in the Medical Association for the Prevention of War in the 1950s.

Penrose developed the Penrose method, a method for apportioning seats in a global assembly based on the square root of each nation's population. Such a voting system is based on the voting power of any voter (measured by the Penrose–Banzhaf index) decreasing with the size of the voting body as one over its square root. See also Penrose square root law.

Penrose was particulalrly interested in different facets of biology, for example fingerprint, demography, and cytogenetics, which were a result of his research into the problems of mental defect, especially Down syndrome. He did intensive research on the latter, communicating the results of his investigations in 1963 and winning the Joseph P. Kennedy Jr. Foundation Award for his contributions to the understanding of the causes of mental retardation.^[7]

Family

Penrose married Margaret Leathes in 1928 and they had four children:

• Oliver Penrose, born 1929, physicist;
• Sir Roger Penrose, born 1931, mathematical physicist and mathematician (with whom Lionel co-authored papers on the Penrose triangle);
• Jonathan Penrose, born 1933, chess player and psychologist;
• Shirley Hodgson (born 1945), geneticist.

After Penrose's death, Margaret married the mathematician Max Newman (1897–1984). She died in 1989.

Penrose' father was James Doyle Penrose. His mother was Elisabeth Josephine Penrose (nee Peckover) and his brother was Sir Roland Penrose, both British artists.^[9][10]

References