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Edward B. Lewis
(1918)
American developmental geneticist who, along with geneticists Christiane
Nusslein-Volhard and Eric F. Wieschaus, was awarded the 1995 Nobel Prize
for Physiology or Medicine for discovering the functions that control
early embryonic development.
Lewis' interest in genetics was kindled in high school. He studied biostatistics
at the University of Minnesota (B.A., 1939) and genetics at the California
Institute of Technology (Ph.D., 1942), where he spent his professional
career. Working independently of Nusslein-Volhard and Wieschaus, Lewis
based his research on studies of the fruit fly, or vinegar fly (Drosophila
melanogaster), a popular species for genetic experiments. By crossbreeding
thousands of flies he was able to establish that genes are generally
arranged on the chromosome in the same order as their corresponding
body segments--e.g., the first set of genes controls the head and thorax;
the middle set, the abdomen; and the final set, posterior parts. This
orderliness is known as the colinearity principle. Lewis also found
that genetic regulatory functions may overlap. For example, a fly with
an extra set of wings has a defective gene not in the abdominal region
but in the thoracic region, which normally functions as a regulator
of such mutations.
Lewis' work on the fruit fly helped to explain mechanisms of general
biological development, such as the causes of congenital deformities,
in humans and other higher organisms. The results of his longtime research
were published in Nature magazine in 1978. He was elected to the National
Academy of Sciences in 1968 and received the National Medal of Science
in 1990.
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