Can i donate blood if i have alpha thalassemia trait?

Yes, but unlikely: A person with Alpha thalassemia trait may be not anemic or mildly anemic. If he is not anemic, he can be a blood donor. However, since he has a more difficult time making hemoglobin (to make new red blood cells), he may not wish to be a blood donor.

Perhaps: The red cross will accept donors with Alpha thalassemia trait, provided that they are not anemic at the time they present (hemoglobin must be 12.5 or higher). There are many variations within the Alpha thal trait group, where some are never anemic and others are often mildly anemic. They will test you for anemia before you donate. If you are not anemic and meet the other criteria you should be ok.

Check for anemia: Check for anemia first which they can do at Red Cross. If its lower than normal , they won't allow you to donate because you might become more anemic

Yes but..: Alpha thalassemia trait will not preclude from donating blood. Anemia (which is checked on intake at the donation center) may preclude you though, depending on how severe the anemia, if present at all, is.