Torbjörn Oskar Caspersson (15 October 1910 – 7 December 1997) was a

Swedish Swedish or ' may refer to: Anything from or related to Sweden, a country in Northern Europe. Or, specifically: * Swedish language, a North Germanic language spoken primarily in Sweden and Finland ** Swedish alphabet, the official alphabet used by ...

cytologist Cell biology (also cellular biology or cytology) is a branch of biology that studies the structure, function, and behavior of cells. All living organisms are made of cells. A cell is the basic unit of life that is responsible for the living and ...

and

geneticist A geneticist is a biologist or physician who studies genetics, the science of genes, heredity, and variation of organisms. A geneticist can be employed as a scientist or a lecturer. Geneticists may perform general research on genetic processes ...

. He was born in

Motala Motala () is a locality and the seat of Motala Municipality, Östergötland County, Sweden with 29,823 inhabitants (41,956 in the entire municipality) in 2010. It is the third largest city of Östergötland, following Linköping and Norrköping. ...

and attended the

University of Stockholm Stockholm University ( sv, Stockholms universitet) is a public research university in Stockholm, Sweden, founded as a college in 1878, with university status since 1960. With over 33,000 students at four different faculties: law, humanities, soci ...

, where he studied medicine and

biophysics Biophysics is an interdisciplinary science that applies approaches and methods traditionally used in physics to study biological phenomena. Biophysics covers all scales of biological organization, from molecular to organismic and populations. ...

Contributions

Caspersson made several key contributions to biology. * In the 1934 he and

Einar Hammarsten Einar Hammarsten (January 4, 1889 in Norrköping - February 16, 1968 in Solna) was a Swedish physician and professor of pharmacy and chemistry at the Karolinska Institute from 1928 to 1957. His area of research was the chemistry of the cell nucle ...

showed that DNA was a polymer. Previous theories suggested that each molecule was only ten

nucleotides Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules with ...

long. * He provided

William Astbury William Thomas Astbury FRS (25 February 1898 – 4 June 1961) was an English physicist and molecular biologist who made pioneering X-ray diffraction studies of biological molecules. His work on keratin provided the foundation for Linus Pauling ...

with well prepared samples of DNA for Astbury's pioneering structural measurements. * In 1936, in his doctoral thesis in chemistry, presented at the Karolinska Institute in Stockholm, he first studied genetic material inside a

cell Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery ...

with an

ultraviolet Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation ...

microscope A microscope () is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. Microscopic means being invisi ...

to determine the nucleic acid content of cellular structures such as the

nucleus Nucleus ( : nuclei) is a Latin word for the seed inside a fruit. It most often refers to: *Atomic nucleus, the very dense central region of an atom * Cell nucleus, a central organelle of a eukaryotic cell, containing most of the cell's DNA Nucl ...

and

nucleolus The nucleolus (, plural: nucleoli ) is the largest structure in the nucleus of eukaryotic cells. It is best known as the site of ribosome biogenesis, which is the synthesis of ribosomes. The nucleolus also participates in the formation of ...

using the

Feulgen reaction Feulgen stain is a staining technique discovered by Robert Feulgen and used in histology to identify chromosomal material or DNA in cell specimens. It is darkly stained. It depends on acid hydrolysis of DNA, therefore fixating agents using stro ...

to stain the DNA. * He worked with Jack Schultz in Stockholm from 1937 to 1939 on protein synthesis is cells and published the work in 1939, where he independent of

Jean Brachet Jean Louis Auguste Brachet (19 March 1909 – 10 August 1988) was a Belgian biochemist who made a key contribution in understanding the role of RNA. Life Brachet was born in Etterbeek near Brussels in Belgium, the son of Albert Brachet, ...

, working out the same problem using a different technique, found that cells making proteins are rich in ribonucleic acids RNA, implying that RNA is required to make

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

s. This was summarised in his book 'Cell Growth and Cell Function' (1950). * He received a personal professorship from the Swedish state in 1944. * He became head of the newly created department for cell research and genetics at the Medical Nobel Institute, at the Karolinska, in 1945. * He was the first to study the giant chromosomes found in insect larvae. * He studied the role of the nucleolus in protein synthesis. * He examined the relationship between the quantity of heterochromatin (chromosomes with few genes) and the rate of growth of cancer cells. * In 1969 when working at the

Karolinska Institute The Karolinska Institute (KI; sv, Karolinska Institutet; sometimes known as the (Royal) Caroline Institute in English) is a research-led Medical school, medical university in Solna Municipality, Solna within the Stockholm urban area of Sweden. ...

, he (with Lore Zech) found that a stain (quinacrine mustard) caused

chromosome A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are ...

s to show light and dark lateral bands along their length. This banding method permits the accurate identification of all 22 autosomes and the X and Y chromosomes. This technique highlighted slight structural abnormalities and specific identification of the extra chromosomes involved in conditions such as

Down's syndrome Down syndrome or Down's syndrome, also known as trisomy 21, is a genetic disorder caused by the presence of all or part of a third copy of chromosome 21. It is usually associated with physical growth delays, mild to moderate intellectual disa ...

(see also

cytogenetics Cytogenetics is essentially a branch of genetics, but is also a part of cell biology/cytology (a subdivision of human anatomy), that is concerned with how the chromosomes relate to cell behaviour, particularly to their behaviour during mitosis an ...

). In 1977 he retired as head of the medical cell research and genetics department at the Karolinska Institute in Stockholm In 1979 Caspersson was awarded the Balzan Prize for Biology "For his fundamental studies on protein metabolism and nucleic acids, culminating in a method for identifying specific bands on individual chromosomes by ultraviolet microscopy, thereby creating a new tool for the study of evolution" (motivation of the Balzan General Prize Committee). He was a member of both the

American Academy of Arts and Sciences The American Academy of Arts and Sciences (abbreviation: AAA&S) is one of the oldest learned societies in the United States. It was founded in 1780 during the American Revolution by John Adams, John Hancock, James Bowdoin, Andrew Oliver, a ...

and the

American Philosophical Society The American Philosophical Society (APS), founded in 1743 in Philadelphia, is a scholarly organization that promotes knowledge in the sciences and humanities through research, professional meetings, publications, library resources, and communit ...

References

* * * * * * * * * * *

External links

Kay Guide at amphilsoc.orgInternational Balzan Foundation
{{DEFAULTSORT:Caspersson, Torbjorn Swedish biologists Stockholm University alumni 1910 births 1997 deaths Foreign Members of the Royal Society Schleiden Medal recipients Swedish geneticists 20th-century biologists Members of the Royal Swedish Academy of Sciences Members of the Royal Society of Sciences in Uppsala Members of the American Philosophical Society