Genes linked to cancers found by scientists

People suffering from a deadly family of cancers were given new hope today after scientists identified 231 previously unknown genes associated with the diseases.

Before the discovery scientists only knew of 33 genes linked to head and neck cancer.

The new research is expected to open doors to diagnostic tests and treatments.

"These new genes should advance selection of head and neck-specific gene targets, opening the door to promising new molecular strategies for the early detection and treatment of head and neck cancer," said study leader Dr Maria Worsham, from Henry Ford Hospital in Detroit, US. "It also may offer the opportunity to help monitor disease progression and a patient's response to treatment."

Head and neck cancer is an umbrella term for tumours affecting the eye, mouth, lip, tongue, throat, voice box, salivary glands, nose and sinuses.

Oral cancers of the mouth, lip and tongue are diagnosed in 5,325 Britons each year and cause 1,851 deaths.

An estimated 85% of head and neck cancers are linked to tobacco use, and the tumours are also associated with drinking alcohol. People who smoke and drink are at greater risk of developing the cancers than those who do either alone.

The new research used a novel approach called "whole genome methylation" to detect altered genes.

DNA methylation is a type of chemical modification to DNA that affects gene activity.

The scientists analysed five DNA samples and focused on 1,043 potential cancer genes.

In total, they identified 231 new genes associated with head and neck cancer.

More than half were present in three or more of the DNA samples, and 20% were found in all five samples.

The findings were presented today at a meeting of the American Academy of Otolaryngology-Head & Neck Surgery Foundation in San Diego, California.

Dr Worsham added: "Abnormal methylation can result in shutting off or silencing gene function. However, treatment with more recent drugs can reverse abnormal DNA methylation patterns, reactivating silenced genes, and restoring normal gene function."