A new cancer test kit will now detect warning signs of the disease years before the first physical symptoms appear, researchers said Monday.

The kit, developed in Singapore, detects the warning signs by detecting minute changes in a patient's DNA.

The early alert test is the joint project of the Institute of Molecular and Cell Biology (IMCB) and electronics giant Hitachi. Both have been working on the project since April 2004.

The kit works by looking at minute changes in the chemical letters, A T and G that make up DNA, the researchers told The Straits Times. In some cancers, C, which refers to the chemical cytosine, undergoes a chemical change that alters its molecular structure.

Scientists believe that lifestyle and environmental factors could be responsible for the change. When cytosine undergoes the change, methylation, the controller genes, lose the ability to produce the correct proteins to prevent tumours, they said.

"Think of it as shutting down your body's innate surveillance system," lead researcher Masafumi Inoue was quoted as saying.

"There is no more controlling influence. It is not only one gene, but several genes, which are silenced when this change occurs."

Gastric cancer, for one, is heavily correlated with DNA methylation, he said. The molecular changes happen before any physical symptoms appear.

The conventional method of screening for DNA methylation examines only a few genes at a time and can be inaccurate.

The IMCB team with Hitachi has devised a test kit that examines multiple areas at one go. The IMBC counts top Japanese cancer researcher Yoshiaki Ito as its adviser.

The cancer diagnostics market is projected to grow from the current $55 million to $93 million by 2008.