I am seeing this diagnosed more and more thse days. Years ago, we had a single member who had dominant beta trait, but I have run into several more on Facebook in the past couple years. It usually should not be considered in the context of thal minor, as it is quite often a more intermedia outcome, with some patients requiring blood transfusions. As far as folic acid, L-methylfolate is far more effective than folic acid. I've been using sublingual B-12 daily, too to help overcome thyroid related fatigue. the enlarged spleen is typical in all forms of thalassemia, as the bone marrow is overactive and much of what is produced are defective red blood cells that are filtered out by the spleen.