Each of our brains are unique. In addition to genetic factors, conditions inside the womb as well as random factors contribute a lot to the way our brains are, and the way we are. No two brains are alike; even the brains of identical twins are considerably different. An interesting find now suggests that there is a connection between the variety in the brain’s neurons and certain genes that can change their position in the genetic code. These so-called jumping genes (or Transposons) may gently scramble the blueprints for the brain. According to Fred Gage from the Salk Institute, this mobility adds an element of variety and flexibility to neurons in a real Darwinian sense of randomness and selection.

Jumping Genes (Courtesy: Saint Anselm College)Transposons have been known for a long time. These are genes that can move around to different positions within the genome of a single cell. This can cause mutations and change the amount of DNA in the genome. This can disrupt the functions of neighboring genes, and thus can directly change some trait in the species, which if beneficial, might aid in its evolution. Jumping genes are found in all living things. Approximately 20 percent of the genetic code in mammals is of the jumping variety! But only a small fraction of these are active – which means they are able to successfully reinsert themselves into a new spot in the code.
The fact that these certain jumping genes can directly affect the brain is what is interesting in Dr. Gage's research, to be published in the journal Nature. He found that a gene called long interspersed nuclear element-1, or L1 for short, jumped positions in cultured brain cells of rats. This is the first time such a jump has been seen in cells other than the sperm or the egg:).
Evolutionarily, this has significant implications. It might be that we owe our intelligence to some so-called jumping gene, and not to a gradual adaptation and improvement as the human species evolved:).