About 6 months after varicose vein surgery, bilateral legs, my first "attack" happened in my legs. I'm sure V. Veins are an indication of venous insufficiency. There's got to be "other" triggers along with the congenital aspect. They HAVE identified the chromosome location for venous disease:
"Genetic research proved in August ,2009 that people with MS have a defective chromosome 6p21.32 venous disease. It was only released to the public on April 28,2010, after the Annual Neurological meeting in Toronto, Canada."
It seems that the Cause of this disease/congenital condition/result of trauma is-proving to be very complicated.