Thalassemia Trait | Thalassaemia Trait
The term thalassemia trait is actually referring to any carrier which carries the genetic trait of either thalassemia alpha or thalassemia beta. For the carrier of thalassemia trait, this does not mean that the carrier is infected with thalassemia but in truth, this only means that the carrier of thalassemia trait will have the potential to inherit this disease to their new born child.
In the early days, the thalassemia trait is mostly found on the people of the Mediterranean region, such as Italians, Greeks and Turks. However, with the population consistently migrating and having inter marriage nowadays, the thalassemia trait can be found almost in every corner of the world, sometimes even in people who have no obvious ethnic relationship with thalassemia.
For the thalassemia trait, the possibilities of inheriting or passing the disease to the next generation are indeed complicated for both alpha thalassemia and beta thalassemia trait. If two carrier of the same genetic type of thalassemia have a new born child, there will be a 25% chance where each of the new born children will be inherited with a severe blood disease. Aside from that, if both of the parents are found carrying the beta thalassemia trait, there will be a 25% chance where each new born child will be affected with Cooley's anemia or thalassemia major, which most of the time means death prior to birth. As for parents who carriers the beta thalassemia trait and the hemoglobin E trait, the newly born child will have a 25% chance of being affected by E beta thalassemia. For beta sickle thalassemia, a newly born child will have a 25% of being affected when one of the parents carries the trait of beta thalassemia whereas the other parent carries the hemoglobin S trait. If both of the parents are found to carry the alpha thalassemia trait and if one of the parents has the "cis" type of alpha trait, the new born child will have a 25% chance being infected with the hemoglobin H disease. Last but not least, if one of the parents carries any kind of thalassemia traits with the other parents having normal hemoglobin, the new born child will have no chance of inheriting any severe blood disease, however, there will be a 50% where the new born child will too inherit a thalassemia trait.
In order to identify whether a person is carrying the thalassemia trait, the first thing to do is to determine the size of that person's red blood cells. By reading at the MCV (Mean Corpuscular Volume), the size of the red blood cells can be determined and from there, if the size of the red blood size falls below 75, the person may be identified with either the alpha thalassemia trait or the beta thalassemia trait. The MCV test can not determine which type of traits the carrier is carrying, in order to further identify the specific trait, the carrier should proceed for a more detailed test in order to determine the type of thalassemia which is infected. As for alpha thalassemia trait, it is harder to identify as it is considered as a silent carrier type and it can only be traced via a special DNA test known as alpha globin DNA mutation analysis.
