Why are homeobox genes similar in all organisms?

Question

Benjamin Alvin · Accepted Answer

Homeobox genes are crucial for very early embryonic development and are involved in cell differentiation and general body pattern.

Homeobox genes are crucial for very early embryonic development and are involved in cell differentiation and general body pattern. They are similar in eukaryotic organisms because every organism needs these essential functions, such as developing body structure.

The image below shows HOX genes (homeotic genes) and how they regulate the body structure of both a fly and a human.

All eukaryotes evolved from a common ancestor with these genes and, while they have not remained identical and have evolved over time, their essential functions have remained relevant thus they have been retained.

You can learn more about homeotic genes in general here and you can read about homeotic genes and body structure here.

Related Socratic questions:
What does it mean when scientists say that living organisms share a universal genetic code?
What do HOX genes do?
How do hox genes regulate development in animals?

Ruby Armstrong · Answer

undefined Homeobox genes are similar in all organisms because they are highly conserved regulatory genes that play fundamental roles in the development of body structures and organs across diverse species. These genes encode transcription factors that control the expression of other genes involved in patterning and determining the body plan during embryonic development. The similarity of homeobox genes among different organisms suggests that they have been evolutionarily conserved due to their crucial roles in development and organismal morphology.