Researchers claimed to have discovered seven new tumour-suppressor genes for head and neck cancers whose role was previously unknown.

The new technique, which the lab recently applied to a screen for a skin tumour gene, takes a fraction of the resources and much less time than the traditional method for determining gene function.

"Earlier methods can take two years per gene in mice. Our technique can assess about 300 genes in a single mouse in as little as five weeks," claimed Daniel Schramek, a post-doctoral fellow at Rockefeller University's laboratory of mammalian cell biology and development here.



In the study, the researchers used RNA interference, a natural process whereby RNA molecules inhibit gene expression.

The non-invasive method avoids triggering a wound or inflammatory response that is typically associated with conventional methods to knockdown a gene in cultured cells and then en-graft the cells onto a mouse.

When the mice grew, the researchers determined which genes, when turned off, were promoting tumour growth, and what they found was surprising.

Head and neck cancers are the sixth most deadly type of cancer worldwide.

"We have demonstrated that RNA interference method is highly useful in the rapid discovery, validation and characterisation of tumour suppressor genes that might otherwise be missed in a genetic screen."

It can be applied to many kinds of cancers, such as breast and lung, the researchers added.

The group hopes to examine the effect in clinical trials in the future, and plans to look at the function of the other six genes their study identified.