London, Jan 30 : Researchers at The University of Texas at Austin have developed a potent gene-networking model for easy identification of disease-causing genes.
The researchers used this gene network technique to spot new genes that control life span and are involved in tumor development in the nematode worm.
For the study, Edward Marcotte, a professor in the Institute for Cellular and Molecular Biology and his colleague, postdoctoral researcher Insuk Lee, collaborated with Andrew Fraser's group at The Wellcome Trust Sanger Institute, and manipulated the newly found genes and succeeded in extending the lives of the worms by 55 pct and reverse the onset of tumors.
Marcotte also expects to use the technique to identify genes for disease and other disorders in humans.
Though, the human genome has been sequenced, but not much is known about the function of about 20,000 genes.
"This is a big step forward in the rational discovery of disease genes. We can use this gene modeling technique to predict the function of new genes and then run experiments to confirm the findings. The process could greatly improve our ability to pinpoint specific genes involved in disease and aid in the development of drugs," Nature genetic quoted Marcotte, as saying.
Such gene networks are models of how all the genes are interconnected within an organism, and Marcotte uses them like an online social network. He tried to find out what new genes do by the genes' connections to others in the network, just like people use online social networking systems to connect with friends and others with similar interests.
"You can think of it like six degrees of separation or a Facebook.com for genes. If you know of a few genes and what they do, their 'friends' probably do something similar, and we can find these through the network," said Marcotte.
In order to construct the worm gene network, Lee combined data from about 20 million experiments worldwide. A visual representation of the network, having the appeal of a work of modern art, is a complex web of lines interconnecting the worm's 16,000 genes.
The researchers looked for genes that cause tumors in the worms, in one set of studies. The tumors are a model for human eye cancer (retinoblastoma) and appear as growths along the length of the worms' bodies.
The researchers found about 170 new genes that could have been involved in the development of tumors, through network searching. Later, researchers at the Wellcome Trust Sanger Institute in Cambridge in the United Kingdom tested the function of the new genes by inactivating them with a technique known as RNAi. The technique imitates the action of a potential drug by disrupting the function of individual genes.
It was found that inactivating 16 of the 170 genes reversed tumors in the worms. Similar studies led the researchers to identify genes that regulate life span in the worms and manipulated the genes to extend the worms' lives by 55 pct.
"This sets the stage for making equivalent networks for the mouse and human genome. Then we hope we can discover genes that are causal for disease conditions in humans," said Marcotte.
The research was published recently online in Nature Genetics.