Tomoko Ohta facts for kids
Quick facts for kids
Tomoko Ohta
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| 太田 朋子, Ōta Tomoko | |
Tomoko Ohta
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| Born |
原田 朋子, Harada Tomoko
7 September 1933 Miyoshi, Japan
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| Nationality | Japanese |
| Education | North Carolina State University University of Tokyo |
| Known for | Development of neutral theory of molecular evolution, and nearly neutral theory |
| Spouse(s) | Yasuo Ohta (m.1960-1972) |
| Awards | Japan Academy Prize (1985) Weldon Memorial Prize (1986) Crafoord Prize (2015) Japan's Order of Culture (2016) |
| Scientific career | |
| Fields | Evolutionary biology genetics |
| Institutions | National Institute of Genetics North Carolina State University Kihara Institute for Biological Research |
| Doctoral advisor | Ken-Ichi Kojima |
| Other academic advisors | Motoo Kimura Hitoshi Kihara |
Tomoko Ohta (太田 朋子, Ōta Tomoko, born Tomoko Harada 原田 朋子 7 September 1933, Miyoshi, Aichi) is a famous Japanese scientist. She is a Professor Emeritus at the National Institute of Genetics. Professor Ohta is known for her important work in population genetics and molecular evolution.
She developed the nearly neutral theory of evolution. This theory helps us understand how tiny changes in our genes happen over time. Tomoko Ohta has received many important awards for her work. These include Japan's highest cultural honor, the Order of Culture, in 2016. In 2015, she also won the Crafoord Prize with another scientist, Richard Lewontin. They won for their amazing discoveries about how much variety there is in our genes.
Contents
Early Life and Education
Tomoko Ohta was born in 1933 near Nagoya, Japan. She grew up in a town called Miyoshi-cho. When she was in 6th grade, World War II ended. After the war, many things changed in Japan, including schools. Boys and girls started going to school together.
Tomoko went to junior high school in Toyota. She became very interested in math and physics. After high school, she went to Nagoya University. She wanted to study medicine but did not pass the exam. So, she transferred to the agriculture department at the University of Tokyo. There, she studied horticulture, which is about growing plants. She graduated in 1956.
After working for a publishing company, she got a job at the Kihara Institute for Biological Research. At this institute, she studied the genetics of plants like wheat and sugar beets.
Studying Abroad
In 1962, Tomoko Ohta got a chance to study in the United States. She joined a graduate program at North Carolina State University. She received a special scholarship called the Fulbright scholarship to help her.
She first planned to study plant genetics. However, she changed her focus to population genetics. This field looks at how genes change in groups of living things over time. She worked with her professor, Ken-Ichi Kojima. Tomoko Ohta earned her PhD in 1966.
Career in Japan
After finishing her PhD, Tomoko Ohta returned to Japan in 1967. She got a research job at Japan’s National Institute of Genetics (NIG). She worked with Motoo Kimura, who was the only expert in theoretical population genetics in Japan at that time.
Tomoko Ohta was promoted to a research position at NIG in 1969. She stayed there until 1996. In 1984, she became a full professor in the Department of Population Genetics at NIG. She later became the head of that department in 1988. From 1989 to 1991, she was also the Vice-Director of the National Institute of Genetics. In 1994, she served as the Vice-President of the Society for the Study of Evolution.
Groundbreaking Research
In the early 1960s, scientists thought that changes in genes (called mutations) were either very bad or very good. Bad mutations would disappear, and good ones would spread. This idea suggested that all living things of the same kind would be very similar genetically.
However, in 1966, two scientists, Richard Lewontin and John Lee Hubby, found something surprising. They discovered that there was a lot more genetic variety among individuals than expected. Motoo Kimura, Ohta's mentor, suggested an idea called the neutral theory of evolution. This theory said that some gene changes were neither good nor bad. They were "neutral" and not affected by natural selection.
The Nearly Neutral Theory
Tomoko Ohta worked with Kimura on his neutral theory. But she started to think that dividing mutations into only "good," "neutral," or "harmful" was too simple. She believed that mutations that were almost neutral still played a big role in evolution.
She developed her own idea, first called the "slightly deleterious model." Later, it became the more general nearly neutral theory of evolution. Her theory was different from her mentor Kimura's idea. Even though they had strong debates, they remained good friends and respected each other's scientific views.
Ohta's theory suggested that most mutations that affect proteins are harmful. But if they are only a little bit harmful (or "nearly neutral"), they can still stay in a population. She also looked at how chance and the size of a population affect these changes.
She showed that in smaller populations, chance plays a bigger role. This means that mutations that are slightly harmful can become common more easily in small groups. This happens through something called genetic drift. It's like rolling a small number of dice – you might get unusual results more often than if you rolled many dice.
In 1974, Ohta and Kimura proposed five main ideas that influence how genes change over time.
Acceptance of Her Ideas
When Tomoko Ohta first shared her Nearly Neutral theory, it was hard to get other scientists to accept it. But over time, more and more evidence came out. In the 1990s and especially in the 21st century, new data from studying proteins supported her theory. Today, her nearly neutral theory is widely recognized as a very important idea in understanding evolution.
Her work is seen as a great starting point for new discoveries in genetics.
Awards and Recognition
Tomoko Ohta's work in molecular evolution has been recognized all over the world.
- 1981 - She received the first Saruhashi Prize, an award for women scientists.
- 1984 - She became an International Honorary Member of the American Academy of Arts and Sciences.
- 1985 - She won the Japan Academy Prize for her studies on population genetics.
- 1986 - She received the Weldon Memorial Prize from the University of Oxford.
- 2002 - She became a Foreign Member of the United States National Academy of Sciences.
- 2002 - The Emperor of Japan honored her as a Person of Cultural Merit.
- 2015 - She shared the Crafoord Prize with Richard Lewontin.
- 2016 - She received the Order of Culture from the Emperor of Japan.
- 2018 - She won the Motoo Kimura Lifetime Contribution Award from the Society for Molecular Biology and Evolution.
See also
In Spanish: Tomoko Ohta para niños
