At our practice you fill in a form which GP then considers. It probably varies depending on practice.  

Here is some more information from cancer research

www.cancerresearchuk.org/.../genetic-testing-for-cancer-risk

I personally decided against genetic testing when I realised that whether or not I had the faulty gene wasn't going to change my behaviour in the future as I was too scared to undergo preventative surgery (even if I were fit enough to do so) and I had already made some other lifestyle changes and was subject to monitoring. As for my children, given a specific risk on their father's side a negative result for me would not have helped them – they are old enough to make their own decision to have testing (or not).  I realised the reason I wanted to know was more for my children's sake than my own. 

People vary a lot in the choice they make about genetic testing and, in order to make that choice, it helps to consider both why you want to know and how it would change things for you if you did.

At our practice you fill in a form which GP then considers. It probably varies depending on practice.  

Here is some more information from cancer research

www.cancerresearchuk.org/.../genetic-testing-for-cancer-risk

I personally decided against genetic testing when I realised that whether or not I had the faulty gene wasn't going to change my behaviour in the future as I was too scared to undergo preventative surgery (even if I were fit enough to do so) and I had already made some other lifestyle changes and was subject to monitoring. As for my children, given a specific risk on their father's side a negative result for me would not have helped them – they are old enough to make their own decision to have testing (or not).  I realised the reason I wanted to know was more for my children's sake than my own. 

People vary a lot in the choice they make about genetic testing and, in order to make that choice, it helps to consider both why you want to know and how it would change things for you if you did.