Theophilus Painter
Encyclopedia
Theophilus Shickel Painter (August 22, 1889 – October 5, 1969) was an American zoologist
known for his work in identifying gene
s in fruit flies (Drosophila
). He did so by applying the incredible detail that had just been discovered to be visible in the giant polytene chromosomes in the salivary glands of Drosophila and other Diptera
n larva
e.
Painter joined the faculty at the University of Texas in 1916 and, except for military duty during World War I, stayed there his whole career. He was, in succession, associate professor, professor and distinguished professor of zoology. He served as acting president (1944-1946) and president (1946-1952) of the University of Texas and retired from active teaching in 1966.
Painter was president of the University of Texas when Texas resident Hermon Marion Sweatt applied and was denied admission due to his race. Subsequently, Painter was the named defendant in the famous civil rights case, Sweatt v. Painter
, 339 U.S.629 (1950),which proved an integral stepping stone in the landmark case Brown v. Board of Education of Topeka, Kansas that held that "separate is inherently unequal" and lead to the integration of America's public schools.
Painter is also known for his early study of human chromosomes. In 1921 he first gave the number 24 for the count of human meiotic chromosome
s. He had tried to count the tangled mass of chromosomes he could see under a microscope in spermatocyte
s in slices of testicle
and arrived at the figure of 24. Others later repeated his experiment in other ways and agreed upon the number of 24. Popular thinking held that if there were 24 chromosomes in spermatocytes, there must be an equal number contributed by the female and the human chromosome number must be 48. This was undisputed for more than 30 years.
Then in 1955 Joe Hin Tjio
, using more advanced techniques, looked at the chromosomes in human somatic
cells and found 46 chromosomes. Together with Albert Levan
, Tjio published this revolutionary finding in early 1956, and the human chromosome number was finally revised. The wonder of Painter's work is not that it was in error but that, given the almost indecipherable mass of chromosomes he examined, he came so very close to the correct human chromosome number.
In 1934 Painter was awarded the Daniel Giraud Elliot Medal
from the National Academy of Sciences
.
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...
known for his work in identifying gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s in fruit flies (Drosophila
Drosophila
Drosophila is a genus of small flies, belonging to the family Drosophilidae, whose members are often called "fruit flies" or more appropriately pomace flies, vinegar flies, or wine flies, a reference to the characteristic of many species to linger around overripe or rotting fruit...
). He did so by applying the incredible detail that had just been discovered to be visible in the giant polytene chromosomes in the salivary glands of Drosophila and other Diptera
Diptera
Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
n larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e.
Painter joined the faculty at the University of Texas in 1916 and, except for military duty during World War I, stayed there his whole career. He was, in succession, associate professor, professor and distinguished professor of zoology. He served as acting president (1944-1946) and president (1946-1952) of the University of Texas and retired from active teaching in 1966.
Painter was president of the University of Texas when Texas resident Hermon Marion Sweatt applied and was denied admission due to his race. Subsequently, Painter was the named defendant in the famous civil rights case, Sweatt v. Painter
Sweatt v. Painter
Sweatt v. Painter, , was a U.S. Supreme Court case that successfully proved lack of equality, in favor of a black applicant, the "separate but equal" doctrine of racial segregation established by the 1896 case Plessy v. Ferguson. The case was also influential in the landmark case of Brown v...
, 339 U.S.629 (1950),which proved an integral stepping stone in the landmark case Brown v. Board of Education of Topeka, Kansas that held that "separate is inherently unequal" and lead to the integration of America's public schools.
Painter is also known for his early study of human chromosomes. In 1921 he first gave the number 24 for the count of human meiotic chromosome
Chromosome
A chromosome is an organized structure of DNA and protein found in cells. It is a single piece of coiled DNA containing many genes, regulatory elements and other nucleotide sequences. Chromosomes also contain DNA-bound proteins, which serve to package the DNA and control its functions.Chromosomes...
s. He had tried to count the tangled mass of chromosomes he could see under a microscope in spermatocyte
Spermatocyte
A spermatocyte is a male gametocyte, derived from a spermatogonium, which is in the developmental stage of spermatogenesis during which meiosis occurs. It is located in the seminiferous tubules of the testis.-Spermatogenesis:...
s in slices of testicle
Testicle
The testicle is the male gonad in animals. Like the ovaries to which they are homologous, testes are components of both the reproductive system and the endocrine system...
and arrived at the figure of 24. Others later repeated his experiment in other ways and agreed upon the number of 24. Popular thinking held that if there were 24 chromosomes in spermatocytes, there must be an equal number contributed by the female and the human chromosome number must be 48. This was undisputed for more than 30 years.
Then in 1955 Joe Hin Tjio
Joe Hin Tjio
Joe Hin Tjio , was a cytogeneticist renowned as the first person to recognize the normal number of human chromosomes. This epochal event occurred on December 22, 1955 at the Institute of Genetics of the University of Lund in Sweden, where Tjio was a visiting scientist.-Early life:Tjio was born to...
, using more advanced techniques, looked at the chromosomes in human somatic
Somatic
The term somatic means 'of the body',, relating to the body. In medicine, somatic illness is bodily, not mental, illness. The term is often used in biology to refer to the cells of the body in contrast to the germ line cells which usually give rise to the gametes...
cells and found 46 chromosomes. Together with Albert Levan
Albert Levan
Albert Levan was a Swedish botanist and geneticist.Albert Levan is best known today for co-authoring the report in 1956 that humans had forty-six chromosomes...
, Tjio published this revolutionary finding in early 1956, and the human chromosome number was finally revised. The wonder of Painter's work is not that it was in error but that, given the almost indecipherable mass of chromosomes he examined, he came so very close to the correct human chromosome number.
In 1934 Painter was awarded the Daniel Giraud Elliot Medal
Daniel Giraud Elliot Medal
The Daniel Giraud Elliot Medal is awarded by the U.S. National Academy of Sciences "for meritorious work in zoology or paleontology published in a three- to five-year period." Named after Daniel Giraud Elliot, it was first awarded in 1917....
from the National Academy of Sciences
United States National Academy of Sciences
The National Academy of Sciences is a corporation in the United States whose members serve pro bono as "advisers to the nation on science, engineering, and medicine." As a national academy, new members of the organization are elected annually by current members, based on their distinguished and...
.