CIC (short for capicua) is a protein that helps control when certain genes are turned off. It acts like a "brake" by attaching to DNA and preventing certain genes from being activated when they’re not supposed to be. This kind of gene controller is called a transcriptional repressor.
CIC plays an important role in how the body develops and functions. It’s especially important in the brain and lungs, where it helps guide normal growth and activity.
CIC was first discovered in the year 2000, when scientists were studying fruit flies. They noticed that when the CIC gene was mutated in fly embryos, the flies developed heads and tails—but were missing most of the middle part of their bodies. Because of this unusual pattern, the scientists named the gene capicua, which means “head and tail” in Catalan, a language spoken in parts of Spain.
Since then, CIC has been found to play key roles in humans too—especially in brain development, cancer, and the immune system. Researchers continue to study CIC to better understand how its loss or malfunction can lead to different diseases.
The CIC gene is found in many living organisms, including fruit flies, mice, and humans—and the gene is very similar across all of them. Because of this, scientists can study CIC in simpler animals and still learn valuable information about how it works in people. These animals are called model organisms, and they help researchers understand how genes like CIC function and what happens when they go wrong.
Both fruit flies and mice are useful in CIC research, but for different reasons:
Mice are much more similar to humans in terms of genetics, brain structure, and body systems. This makes them ideal for studying how CIC affects complex areas like the immune system or the nervous system.
Fruit flies are smaller, cheaper, and easier to keep in large numbers. They grow and reproduce very quickly, so scientists can study many generations in a short time. This makes them great for early discovery and genetic research.
By combining studies from both mice and flies, researchers can get a better, more complete understanding of CIC—how it works, and how it might be involved in diseases like cancer, autoimmunity, or neurodevelopmental disorders.