The Nobel Prize in Physiology or Medicine 1995


The Nobel Assembly at the Karolinska Institute in Stockholm, Sweden, has awarded the Nobel Prize in Physiology or Medicine for 1995 to Edward B. Lewis, Christiane Nüsslein-Volhard and Eric Wieschaus for their discoveries concerning “the genetic control of early embryonic development”.

From Egg to Adult Fly

The development of a             Drosophila

The adult fly consists of head, 3 thoracic segments, 8 or 9 abdominal segments and tail. The individual segments develop differently during embryogenesis – but how is this done? Which genes control these events? How many are they? Do they cooperate or are they working independently of each other?


How Early Embryos are Formed

Christiane Nüsslein-Volhard and Eric F.Wieschaus identified and classified 15 genes of key importance in determining the body plan and the formation of body segments of the fruit fly Drosophila melanogaster. More about Nüsslein-Volhard's and Wieschaus discoveries
More about Lewis' discoveries
Edward B.Lewis studied the next step – homeotic genes that govern the development of a larval segment into a specific body segment. Homeotic means that something has been changed into the likeness of something else. Lewis found a co-linearity in time and space between the order of the genes in the bithorax complex and their effect regions in the segments.

To cite this section
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