What is genetic health testing?

Everyone's DNA can, if interpreted accurately, give clues to the likelihood of developing certain diseases. By taking samples of genes it becomes possible to identify some diseases that individuals have an enhanced risk of developing. At least 8 per cent of breast cancer cases, for instance, are caused by specific genetic mutations. Identifying these before the onset of a disease will give people the chance to lead a lifestyle that will minimise the chances of the disease taking hold

How accurate is it?

At present the science is in its infancy and the genes that have a direct influence on diseases are still being discovered. Barely a week goes by without researchers announcing a new link between genes and disease - a rate that says as much about what scientists don't know as about what they do. However, once rogue genes such as the breast cancer BRCA1 and BRCA2 mutations are discovered, they can be reliably identified

Why does it raise concerns about designer babies?

Parents who know they are at risk of passing on a crippling or deadly disease can decide to screen embryos before they develop into a baby. Objections are limited at present because the children are saved from developing diseases. But there are concerns that in the future parents will be able to demand screening for other attributes such as intelligence or beauty

Who gets genetic tests?

For the most part genetic tests are carried out when there is a reason to suspect that specific mutations are present. If several generations of a female line are known to have had breast cancer, doctors may well think it prudent to test for genes linked to the disease. Other tests are carried out by private companies that offer a profile of customers' genes and then gauge susceptibility to a range of conditions, including dementia and obesity

Who pays?

The NHS will pay for genetic tests, after a GP referral, in families where there is a serious risk of a range of inherited diseases. These include inherited breast cancers and Huntington's disease. Screening of embryos is more likely to have to be paid for by individuals. Primary care trusts will consider whether to pay for the procedure case by case. For those with fertility problems the IVF stage can be charged to the NHS

Does having taken a genetic test affect insurance?

For now, no. There is a moratorium until at least 2014 preventing insurance companies from using the results of predictive genetic tests. It was introduced so that no one would be put off from being tested for hereditary diseases. In the future it is possible that the moratorium will be lifted, in which case premiums could go up or down depending on a person's genetic make-up

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