The researchers from the Peninsula Medical School, Exeter in the UK, say the research has revealed an insight into how the body grows and may also explain how conditions such as osteoarthritis and cancers develop.

The team discovered the "height gene" last year after examining DNA samples from more than 30,000 people across Europe and identified the regions of code which make a difference of up to six centimetres in height.

Researcher Dr. Tim Frayling says the number and variety of genetic regions found, show that height is not just caused by a few genes operating in the long bones.

They say height is 90 per cent determined by genes, rather than external factors such as diet and suggest that their research implicates genes that explain a whole range of important biological processes.

Dr. Frayling says the identification of the genes which affect normal growth could lead to an understanding of the processes that lead to abnormal growth such as tumours and not just height disorders.

It appears that some regions of the code identified regulate basic cell division, which could be useful for research into cancer, which causes uncontrolled division; others are concerned with cell-to-cell signalling, which is important in the early development of embryos.

Lead author Dr. Mike Weedon, says there may be more than a hundred genes which affect our height, many of which will work in surprising or unpredictable ways.

He says the challenge is to understand how they influence growth in the body and this could open up new avenues for treating a range of diseases.

The study is published in the journal Nature Genetics.

Half of the new loci identified by Dr Frayling and colleagues contain genes whose functions are well documented. Some help regulate basic cell division, which may have implications for cancer research: unregulated cell division can lead to the growth of tumours. Other genes are implicated in cell-to-cell signalling, an important process in the early development of embryos in the womb. Yet others are so-called "master regulators", acting as switches to turn genes elsewhere in the genome on or off.

One locus in particular is also implicated in osteoarthritis, the most common form of arthritis involving the effects of wear and tear on the body's structures. This locus reinforces a similar link identified by a previous study, and may be involved in the growth of cartilage.

However, of the twenty loci identified by Dr Frayling and colleagues, half contain genes about which little or nothing is known. The researchers compare these findings to their work last year which identified the first common gene for obesity, the FTO gene. Even though the gene has been shown without a doubt to be influence body size, its role is still unclear.

"There may be more than a hundred genes which affect our height, many of which will work in surprising or unpredictable ways," says Dr Mike Weedon, lead author on the paper. "The challenge now for us is to understand how they influence growth in the body. This could open up new avenues for treating a range of diseases."

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