It sounds like you have done a great deal of research about Marfan syndrome. It is important to have a complete exam specific for Marfan syndrome to completely rule out or diagnose the condition.
A medical geneticist would be the appropriate type of physician to perform a complete exam. As you know, Marfan syndrome is a connective tissue disorder that affects many parts of the body including the eyes, skeleton, heart, and blood vessels. You can find a medical geneticist through the American College of Medical Genetics (ACMG). As part of the work-up, an opthalmalogist performs a slit-lamp examination, looking for lens dislocation. You mentioned that you had an echocardiogram that was normal. You may want to request a copy of that report to see if your aorta was measured. If not, then an echocardiogram with a measurement of the aorta is typically ordered as part of the evaluation for Marfan syndrome.
Marfan syndrome runs in families in an autosomal dominant manner. This means that someone with Marfan syndrome has 50% chance of passing this condition on to each child he or she has. Inheritance is not affected by gender.