Not every gene has something useful to contribute. In fact, most of your genes, for most of the time, are silent.
This is crucial if an organism has any chance of functioning properly - different cells develop in different ways as a result of a particular combination of active and inactive genes.
The alternative would be catastrophic, like repeatedly cramming all the notes from an entire symphony into a single beat and hoping what emerges sounds like music.
One of the more drastic ways in which this genetic silence can be achieved is by permanently gagging a gene, in a process called DNA methylation.
It stops females from expressing the genes on their extra X-chromosome, shuts down so-called parasitic genes and may have an important role in directing gene expression during development.
In essence, methyl molecules bind to a base pair close to the gene to be silenced in combination with an enzyme that prevents transcription factors from reading the DNA, like chemical noise abatement officers.
At the University of Edinburgh, Adrian Bird has been studying these enzymes since discovering the first one, known as MeCP2, less than ten years ago.
Recent work by a team in the United States has implicated the gene behind this particular enzyme as being linked to a serious medical condition.
It seems that if a girl has a mutant MeCP2 gene on her X-chromosome, she will develop Rett syndrome by the time she reaches 18 months, leaving her with severe mental and physical disabilities.
One in 10,000 women has thecondition. Boys with the condition are stillborn.
Professor Birdhas been trying to create a "knock-out" mouse model ofthe disease, which could enable scientists to understand this illness.
Steve Farrar
A public debate on the new genetics will beheld at 7pm on Mondayin hall one, International Conference Centre, Birmingham.