Telomeres are the protective caps at the ends of chromosomes in cells. Chromosomes carry the genetic information. Telomeres are buffers. They are like the tips of shoelaces. If you lose the tips, the ends start fraying.

If we think of our chromosomes - they carry our genetic material - as being like shoelaces, I work on the plastic tips at the end that protect them.

The most dangerous cancer cells are actually the ones that are more like stem cells, which have this ability to produce themselves over and over again. More and more cancer biologists say stem-cell-like cells in cancers are the most dangerous.

Ageing is so many different things, and cells being able to self-renew is part of the picture but not all of it.

We're involved in a very large study that's federally funded and being done with Kaiser Permanente, and saliva is a very non-invasive way to get cells from the body.

Basically, when you look at different types of cells, such as fibroblasts, which form connective tissue, or epithelial cells, from saliva, you see general correlations within a person. If telomeres are up for one cell type, they're up for others overall.