After hearing about my breast cancer diagnosis, a friend of mine revealed to me that she has a strong history of breast cancer in her family and would strongly consider bilateral prophylactic mastectomy should she test positive for one of the BRCA genes.  She says this is always something that she has worried about and that it would be a gift if she could just know one way or the other.  However, she's very concerned that if she gets genetic testing and indeed tests positive, it could affect her health insurance, either causing her to be dropped or having this designated as a "pre-existing condition."  Also, she's self-employed and has private individual health insurance vs. group, which already presents its own difficulties. 

Does anyone know how a positive test affects insurance?  (We know that this could vary from state to state.  We reside in Connecticut.)  Thanks in advance for any feedback, suggestions, or resources that you can provide.  It would be wonderful if she could proceed with such testing with confidence and finally achieve some peace of mind one way or the other.