To answer your question about family history, I have 2 sons, the older one suffers from BO, and has controlled it significantly with the TMAU protocol.  The younger son is lactose intolerant, and he has bad breath and body odor form time to time, depending on his diet and exercise levels.  In both my sons, a high choline diet produces at least bad breath, and especially in my older son, it can produce an extremely strong odor that is very difficult to describe.  At times it seems very much like sewage, other times sulfur-like, and other times like dead fish.  He basically did the following protocol recommended by the National Institute of Health for TMAU, and in a matter of less than 6 months, his odor is almost completely gone, except for a very mild bad breath.  http://curezone.com/forums/am.asp?i=1115456#i1

http://curezone.com/forums/fm.asp?i=1115286#i

This diet doesn’t work for everyone, but it does for both my sons.  

My younger son seems to have his odor under control because he runs an average of 4 to 9 miles a day, 6 days a week, and I believe he sweats out all his toxins.  Even so, if he eats a high choline diet repeatedly for days, he will smell very bad, especially after running before showering.  After a week or 2 of not running, he starts with a mild bad breath that gradually increases until he starts running again.  

There are 2 other members in my family that suffer from the same odor at varying degrees, my father and my sister’s son.

As a teenager, I did have bad breath that was almost impossible to control, and I might have it every once in a while still (I'm 54 years old).  It improved after I had my tonsils removed at the age of 18 because I had tonsil stones.  I had underarm odor that was completely controlled with deodorant.  At times, I’ve had foot odor, but my podiatrist told me it was a bacterial infection and gave me an antibacterial powder called On Your Toes, which took care of the problem.  She explained that there is a balance between bacteria and fungus on the feet, and if that balance goes off, then you can have smelly bacterial infection or not so smelly fungal infection.  You have to know which you are treating first because it can make it worse.

So based on all this, I do believe that there has to be a defective gene in our family that affect some metabolic enzyme that causes BO.  I’m probably more a carrier than a true sufferer compared to my older son.