Hair restoration specialists in the US are to start offering DNA tests to inform people whether they are likely to go bald, before it happens.

The test is simple: the patient simply provides a saliva swab, which is sent to the lab for analysis by experts who look for genetic variations on the x chromosome, which suggests likely hair loss.

Clients are then informed whether they have a low-risk or high risk of baldness. Low risk means clients have a 80 per cent chance of having a full head of hair at 60 years old, while high risk means there is a 60 per cent risk of severe baldness by 40 years of age.

People as young as 15 years old are putting themselves forward for the tests. They hope to find out the reality of their hair loss situations while it’s possible they may be able to seek preventative treatment.

Dr Alan Bauman, one of the experts offering the DNA tests, says they offer information which can then be used as a base on which to decide whether preventative measures can be taken. He adds, “this just gives another piece of information and then you decide with your doctor what you want to do.