Hox Genes (Body-Plan Genes)
Lewis, Nüsslein-Volhard and Wieschaus found the genes that lay out a fly's body; the 1983 homeobox discovery showed the same genes in mice and humans (Nobel Prize 1995).
Open in the interactive tree →William Bateson coined 'homeosis' in 1894 for body parts replaced by others, and Calvin Bridges found the first such fruit-fly mutant in 1915. Edward Lewis, Christiane Nüsslein-Volhard and Eric Wieschaus identified the key body-plan genes of Drosophila, and in 1983 teams in Basel and Indiana independently found a shared DNA stretch, the homeobox, in several of them; it turned up in frogs, birds and mammals. Mice and humans have 39 Hox genes in four clusters, and a chicken Hox gene can stand in for its fly counterpart, which shows the system is about 550 million years old. Evolutionary developmental biology grew from this link between genes, embryos and evolution.
Prerequisites
- Evolution by Natural Selection1859Shared control genes show how animal body plans are inherited and changed.
- Chromosome Theory of Heredity1915The first homeotic mutant was found in Morgan's fruit-fly lab in 1915.
- Genetic Engineering1973Cloning let labs isolate the shared homeobox DNA in 1983.
- Sanger DNA Sequencing1977The homeobox was spotted by comparing DNA sequences of cloned fly genes.
Unlocks
- Predicting Traits from DNAopenHox genes were the first clear case of a few genes steering whole body shapes.