At present there are over 7,000 genetic conditions which are responsible for one in every one hundred new-borns being born with a serious illness.
We are all carriers, on average, of between five and ten mutations involved in rare, potentially serious diseases that we can pass on to our offspring. In the majority of cases we are not even aware, as carriers may not have any symptoms. For this reason, there are an increasing number of couples interested in having this type of test carried out.
Being a carrier of these mutations does not necessarily mean that you have the disease. However, it would be possible for your children to have the disease if your partner is also a carrier of these mutations in the same gene. In these cases, the likelihood of having a child affected by the disease is 25%.