Albert Lasker
Basic Medical Research Award
Edward Lewis
For fundamental research on the Bithorax complex, which established the role of homeotic genes in the development of cell patterns and provided a foundation for current studies of embryonic development.
In fundamental discoveries made over the last 40 years, Dr. Lewis has laid the foundation for most of what is known today about the evolution, structure and function of control genes, which regulate development of specific regions of the body. Dr. Lewis's revolutionary investigations have also provided methods and materials for analyzing gene function, laying the groundwork for late discoveries of control genes in other organisms, especially vertebrates.
Dr. Lewis is particularly known for his use of the fruit fly, Drosophila, to study how genes determine heredity. Beginning with a small number of viable mutants of the fruit fly, he discovered what he called the Bithorax complex, a cluster of genes in the fly that controls how the body segments develop. Beginning in the late 1940s, Dr. Lewis showed that mutations in Drosophila that lead to striking abnormalities, such as embryos with multiple thoraxes or flies with four wings instead of two, are organized in giant clusters.
This work established the concept that single genes can control the development of specific regions of the body. Further, Dr. Lewis established a direct relationship between the tandem repeat structure of the Bithorax complex genes and their orderly expression in the body. He then made what 30 years ago was considered a radical proposal: that such gene clusters evolved by repeated duplication of a single ancestral gene and that these clusters in modern organisms would show traces of their common origin.
Dr. Lewis's studies launched a new area of investigation into how genes regulate the entire course of growth of a living organism. Over the past decade, using new techniques of molecular biology, scientists have built on his observations about development. In particular, they have identified within the DNA of each gene of the giant clusters a region that differs very little from organism to organism, called the "homeobox." The nature of the homeobox and its precise function is a widely investigated area in developmental biology today. There is considerable speculation that it acts as a kind of master regulator of development.
To Dr. Edward Lewis, for his discovery of the Bithorax complex, through research on the fruit fly, which led to the establishment of fundamental principles for analyzing gene function in developing organisms, including human beings, this 1991 Albert Lasker Basic Medical Research Award is given.
Christiane Nüsslein-Volhard
For charting new paths in developmental biology through investigations which led to the discovery of nearly all genes responsible for organizing basic body patterns.