Halloween genes

All of the genes code for cytochrome P450 enzymes in the ecdysteroidogenic pathway (biosynthesis of ecdysone from cholesterol).

Ecdysteroids such as 20-hydroxyecdysone and ecdysone influence many of the morphological, physiological, biochemical changes that occur during molting in insects.

[5] First elaborated by research groups led by Wieschaus and Nüsslein-Volhard in the early 1980s, the name was coined to collectively name a series of Drosophila embryonic lethal mutations associated with defective exoskeleton formation.

Early research showed that when one of the Halloween genes was mutated, fly embryos would die before the exoskeleton was created.

[6] The disembodied gene (Cyp302a1) codes for a cytochrome P450 enzyme that adds a hydroxyl group to the carbon-22 position of 2,22,dE-ketotriol to make 2-deoxyecdysone.