Researchers have cracked the code behind orange cats’ vibrant fur, revealing a specific DNA deletion on the X chromosome responsible for this unique coloration.
The Genetic Secret Behind Orange Cats
Domestic cats are known for their vibrant fur colors, but have you ever wondered what makes an orange cat truly orange? Researchers have finally cracked the code by identifying a specific DNA deletion on the X chromosome that leads to this unique coloration.
Orange cats owe their vibrant coat color to a specific genetic combination.
The production of the orange pigment, phaeomelanin, is triggered by the presence of the orange gene, which codes for the enzyme tyrosinase.
This gene is located on the X chromosome, making it more common in male cats since they have only one X chromosome.
Female orange cats are usually tortoiseshell or calico, as they need to inherit two copies of the orange gene, one from each X chromosome.
The Role of Arhgap36
According to two independent studies published in Current Biology, the genetic instructions for ginger fur reside in the X sex chromosome. Most orange cats are male because they usually have just one X chromosome, which is active in each cell. Female cats normally have two X chromosomes, both of which would need to carry the orange trait for a girl to be fully ginger.
However, most other mammals, including big cats like tigers, don’t acquire ginger hair based on sex, hinting that domestic cats possess an unusual mutation. The mutation involves a deletion near a gene called Arhgap36, which boosts production of the protein encoded by this gene in pigment cells.
ARHGAP36, or Rho GTPase activating protein 36, is a gene that plays a crucial role in regulating cell signaling pathways.
It acts as a negative regulator of Rho GTPases, which are essential for various cellular processes such as migration, proliferation, and differentiation.
Mutations in the ARHGAP36 gene have been linked to several diseases, including cancer and neurodegenerative disorders.
Research has shown that dysregulation of ARHGAP36 can lead to uncontrolled cell growth and tumor formation.
How It Works
The deletion prevents genes needed to create the brown-black pigment from turning on, leaving more easily made yellow-red pigment to be produced instead. This unique mechanism is responsible for the characteristic orange coloration seen in orange cats. The Arhgap36 protein plays a crucial role in regulating this process, and its increased production leads to the desired color effect.
A Shared Mutation
A team of researchers analyzed DNA from about 30 cats to find variations shared exclusively by those with orange fur. They discovered that almost all orange cats had the same deletion near the Arhgap36 gene, while non-orange ones lacked it. The study suggests that this mutation was passed down from one ancestral cat and has been present in domestic cats for over 900 years.
New Insights
Before these studies, researchers didn’t know about the role of Arhgap36 in coloration. It’s mostly active in hormone-producing organs like the pituitary gland. The discovery of its involvement in ginger hues is unique to domesticated felines and provides a fascinating glimpse into the genetic secrets behind our beloved pets.
Conclusion
The identification of the genetic secret behind orange cats offers a new perspective on the biology of this distinctive coloration. By understanding the role of Arhgap36, researchers can gain insights into the evolution of domestic cats and their unique characteristics. This study highlights the importance of continued research into the genetics of animals, which can lead to a deeper appreciation for the complex mechanisms that govern our world.
Animal genetics is a branch of biology that studies heredity and variation in non-human organisms.
It involves the study of genes, chromosomes, and DNA to understand how traits are passed down from one generation to the next.
Animal genetics has numerous applications in agriculture, conservation, and medicine.
For example, genetic testing can help identify inherited diseases in animals, while selective breeding can improve desirable traits such as milk production or egg-laying capacity.
- sciencenews.org | What gene makes orange cats orange? Scientists figured it out
