A new class of cancer-causing genes is found

American scientists say they've identified a whole new class of cancer-causing genes.

In recent years, researchers described a novel class of genetic regulators, called microRNAs, that influence normal growth and development. But in this latest research, scientists at Cold Spring Harbor Laboratory in New York and the University of North Carolina at Chapel Hill found that microRNAs also play an important role in &to=http:// english.pravda.ru/science/2005/05/12/59704.html ' target=_blank>human cancer.

The researchers discovered that certain of these gene types are overexpressed in malignancies ranging from lymphomas to colon cancer.

"These studies change the landscape of cancer genetics by establishing the specific microRNAs expressed in most common cancers and investigating the effects of microRNAs on cancer development and cancer genes," Dr. Paul Meltzer, a National Human Genome Research Institute cancer expert, said in a prepared statement, informs the Forbes.

According to the New York Times, the findings concern micro-RNA's, which are tiny snippets of genetic material that help dampen the activity of other genes. The material was discovered in the early 1990's, in the roundworm, and in recent years scientists have been finding them everywhere, including at least 200 in human cells.

The mere discovery has altered views of RNA's importance in regulating the working of genes. The previous view was that genes, which are made of DNA, are the recipes for protein, which make up much of the structure of cells and perform most of the functions. In this scheme, RNA, a sort of chemical cousin of DNA, acted mainly as a messenger dispatched by DNA to carry the recipe for a protein to the cell's protein-making machinery.