What Treatment Should I Take For Mthrfr Mutation Post A Surgery For Clot And A Family History Of DVT ?

2yrs ago a clot was found in my left femoral.I was placed on Warfarin and had an IVC filter placed,prior to a surgical procedure.It took nearly a year @ 10mg per day to get my INR to 1.3. The first clot was resolved but more were found.Recently I moved to FL and my new GP diagnosed me w polycythemia,based on the levels of my lab results.Then I went to a hemotologist who says its not poly... but I do have the mthrfr mutationWhat is going on, what can I do?,my Mother a pulmonary embolism,. My Grandmother died of a stroke,my brother is currently being treated for a clot in his calf, and worst of all my 12 yr old nephew had to be airlifted to LomaLindaChildrens after a clot was found in his neck.He tested positive for the leiden factor.I was negative. i would really appreciate any info on what it is Im dealing w.I also have a daughter who seems well but has not been tested,yet. I turned 40 2 days ago.I dont mean to bombard you,I hope you understand and appreciate that I am desperate for info. Unfortunately the drs here are giving me conflicting opinions and info. PLEASE HELP!!!