Hox genes don't evolve as far as the eye can see...

Scientists Discover Common Genetic Mechanisms in Sea Anemones and Humans

Scientists have discovered that sea anemones and humans share a common set of genetic mechanisms that control the development of body segments. This finding, published in the journal Nature, provides new insights into the evolution of animal development.

Sea anemones are simple, radially symmetrical animals that lack bones, brains, and a complete gut. Humans, on the other hand, are complex, bilaterally symmetrical animals with a highly developed nervous system. Despite their differences, both sea anemones and humans develop segments during their early development.

In the study, researchers from the University of California, Santa Cruz, identified a set of genes that are involved in the development of segments in sea anemones. These genes are also found in humans, and they play a similar role in segment development.

The researchers also found that the expression of these genes is controlled by a group of genes known as Hox genes. Hox genes are master regulatory genes that play a critical role in the development of body plans in all animals.

The findings of this study suggest that the genetic mechanisms that control the development of segments were already present very early in the history of animal life and with no evolutionary history. Imagine that.

The researchers say that their findings could have implications for understanding human diseases. For example, mutations in Hox genes have been linked to a variety of developmental disorders, such as spina bifida. By understanding how Hox genes work in sea anemones, researchers may be able to better understand how they work in humans and develop new treatments for these disorders.

The study's findings also provide new insights into the evolution of animal body plans. By comparing the development of sea anemones and humans, researchers can gain a better understanding of how the different body plans of these animals evolved. This knowledge could help scientists to develop new models for studying the evolution of other animals, including extinct animals.

Hox genes are a group of genes that are essential for the development of body plans in animals. They are found in all bilaterian animals, which means that they were present in the multiple LECA branches. LECA branches are thought to have arrived fully formed with no evolutionary history  around 600 million years ago, at the base of the "bush of life", one of lifes unexplained "big bangs."


Hox genes are expressed in a specific order along the body axis, from head to tail. This order is determined by the position of the genes on the chromosome. The different genes in the Hox gene cluster are responsible for the development of different body parts, such as the head, thorax, and abdomen.


Hox genes have also been implicated in the Lamarckian evolution of new body plans. For example, the Hox genes of vertebrates are thought to have played a role in the evolution of the tetrapod body plan, which has four limbs.

The presence of Hox genes in the LECA suggests that the basic body plan of bilaterian animals was already established at this early stage in evolution. This is further supported by the fact that the Hox gene clusters of different bilaterian animals are very similar.

Hox genes code IDPs (intrinsically disordered proteins) that are guided by epigenetics. Epigenetic modifications, such as DNA methylation and histone modification, can regulate the expression of Hox genes without NeoDarwinism  This regulation is essential for normal development, as Hox genes play a key role in determining the body plan of an organism.

In humans, there are 4 clusters of Hox genes, each of which contains about 13 genes. These genes are located on different chromosomes and are arranged in the same order as they are expressed in the developing embryo. This order is known as the Hox code and it is essential for the correct development of the body.

For example, Hox genes in the first cluster are responsible for the development of the head and neck region. Hox genes in the second cluster are responsible for the development of the trunk region, and so on.

Last year a scientist won the Nobel for showing the epigenetic Hox gene difference between Neanderthal and humans.

Overall, Hox genes are essential for normal development and epigenetic modifications play a key role in regulating their expression.

Here are some additional details about Hox genes and epigenetics:

  • Hox genes are transcription factors, which means that they bind to DNA and regulate the expression of other genes.

  • Epigenetic modifications are chemical changes that can be added to DNA or histone proteins.

  • Epigenetic modifications can affect how genes are expressed, without changing the underlying DNA sequence.

  • Epigenetic modifications can be inherited from parents to offspring.

  • Epigenetic modifications can be influenced by environmental factors, such as diet, stress, and exposure to toxins.

The basic mechanisms of animal development have not changed for billions of years. No Darwinian evolution for billions of years. This goes against Darwin's thoughts of gradualism. These mechanisms are responsible for the development of all animals, from the simplest jellyfish to the most complex humans.

The basic mechanisms of animal development include:

  • Cell division: Cells divide to create new cells, which are the building blocks of all tissues and organs.

  • Cell differentiation: Cells differentiate to become specialized cells with specific functions.

  • Morphogenesis: Morphogenesis is the process of shaping and forming the body. It involves the movement of cells and tissues, as well as the growth and differentiation of cells.

  • Gene regulation: Gene regulation is the process of controlling which genes are turned on and off. This process is critical for ensuring that the right cells differentiate into the right tissues and organs.

These mechanisms have been conserved for billions of years because they are largely controlled by IDP which can resist Darwinian mutations over billions of year's. NeoDarwinism was based on the one gene-one structured protein model which allowed natural selection. As IDP have Intrinsically Disordered Regions that can absorb mutations without change they are outside of NeoDarwinism structured change model.

However, the basic mechanisms of animal development using IDPs can be modified to produce new and diverse animal forms. This is done through epigenetic modification of Hox genes. The basic mechanisms of animal development are a fascinating and complex topic. By understanding how these mechanisms work, we can gain insights into the origins of animal diversity and the evolution of new animal forms. 


The "common genetic toolkit" refers to the shared set of genes and genetic processes that are found in all living things.  There are a number of processes that can lead to the exchange of genetic material between organisms, even without common ancestry. These processes include:

  • Transposable elements (TEs) are mobile genetic elements that can insert themselves into the genomes of other organisms. TEs can be inherited from a common ancestor, but they can also be transferred between organisms through horizontal gene transfer (HGT).

  • Intragenomic duplication is the process by which a segment of DNA is duplicated within the genome of an organism.  It can lead to the development of new genes and genetic functions.

  • Horizontal gene transfer (HGT) is the process by which genetic material is transferred between organisms that are not closely related. HGT can occur through a variety of mechanisms, including direct cell-to-cell contact, virus-mediated transfer, and gene transfer through the environment.

  • Epigenetics is the study of changes in gene expression that are not caused by changes in the DNA sequence. Epigenetic changes can be inherited from parents to offspring, and they can be influenced by environmental factors such as diet, stress, and exposure to toxins.

These processes can all lead to the Lamarckian evolution of new genetic traits, even in organisms that do not share a common ancestor. As a result, the "common genetic toolkit" can be a misleading indicator of common ancestry. 

Here are a few articles that discuss the potential for Hox proteins to be IDPs:

  • "Intrinsically disordered proteins in development and evolution" by J.K. Jang and J.A. McCammon (2007)

  • "The intrinsically disordered nature of Hox proteins and their role in development" by M.J. O'Connor and M.R. Capra (2009)

  • "The role of intrinsically disordered proteins in transcriptional regulation" by M.F. Goodman and J.D. Forman (2011)



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