Segmentation gene

Segmentation genes have been documented in three taxa: arthropods (i.e. insects and crabs),[2] chordates (i.e. mammals and fish), and annelids (i.e. leeches and earthworms).

[6] Rare variants in segmentation genes can cause changes in appearance of differing severity depending on its type.

Maternal effect genes encode factors like messenger RNA needed for early development such as cell division.

[10] This creates a concentration gradient where bicoid expression is highest in the anterior and gradually decreases towards the posterior.

[16] Lastly, the gap genes also play a role in later development such as giving rise to neurons along with formation of muscles and the gut.

Lastly, certain segment polarity genes like wingless are involved in the planning and development of body parts such as the wings.