Scientists have identified specific genetic variants associated with biological ageing in humans.

Biological ageing, as distinct from chronology ageing, includes changes in the physical structure of the body as well as changes in the performance of motor skills and sensory awareness.

The team analysed more than 500,000 genetic variations, across the entire human genome, to identify the variants which are located near a gene called TERC.

These findings were done by researchers from the University of Leicester (U-L) and King's College London, working with University of Groningen in the Netherlands.

Nilesh Samani, cardiology professor at U-L, who co-led the project, explained that there are two forms of ageing -- chronological ageing i.e. how old you are in years and biological ageing whereby the cells of some individuals are older (or younger) than suggested by their actual age.

'There is accumulating evidence that the risk of age-associated diseases including heart disease and some types of cancers are more closely related to biological rather than chronological age,' said Samani.

'What we studied are structures called telomeres which are parts of one's chromosomes. Individuals are born with telomeres of certain length and in many cells telomeres shorten as the cells divide and age. Telomere length is therefore considered a marker of biological ageing.'

'In this study what we found was that those individuals carrying a particular genetic variant had shorter telomeres i.e. looked biologically older,' said Samani.

These findings were published in Nature Genetics today.