non-deletion thalassemia

I have seen very little information about this form of thalassemia.  Is it because it is incredibly rare?  Anyone know what the symptoms are for this form of thalassemia?  How does it compare in severity to the other forms of thal? 

p.s. Friday I will be doing my presentation on thalassemia to my class.  I am going to encourage my class mate to donate more blood. 

I also thought I might quote some of you from some of my previous questions if thats okay.  I really want to help the class understand more than just a few facts about the genetic disorder.

Hi Emersive,

I am not an expert in this field, but I am a thal carrier and a parent of a thal major child who is compound heterozygous.

The mutations that my wife and I have (different mutations, that's why our daughter is compound heterozygous instead of homozygous), and what our daughter inherited from us are both non-deletional mutations.

The mutation that I have, IVS-I-5 (G->C), is very common and is termed a beta+ (severe) mutation. So, are the other nondeletional mutations.

Please refer to the following website for information on various types of thal mutations (it is a bit old ... but I think the info in there may be still relevant). This material is from the book A Syllabus of Thalassemia Mutations (1997) by Titus H.J. Huisman, Marianne F.H. Carver, and Erol Baysal, published by The Sickle Cell Anemia Foundation in Augusta, GA, USA. Copyright © 1997 by Titus H.J. Huisman.

http://globin.cse.psu.edu/html/huisman/thals/contents.html

Regards,

Bostonian

So generally speaking what is the difference between a non-deletional variation of Thalassemia and a deletional variation?

Is it just that the non-deletional variations are damaged alpha or beta genes?  Where as the deletional variation is that they are just missing?

What is most severe?  Is there a major difference as far as phenotypic expression between a non-deletional beta-intermedia and a deletional beta-intermedia thalassemic?  (just as an example)

Some mutations render the gene useless so it can't be generally said that deletion is necessarily any worse than a mutation. Some mutations will cause a condition as serious as deletions. There are over 200 known mutations of the beta hemoglobin gene. As researchers slowly identify and chart these mutations they may get a better idea of what to expect by looking at the genes and combinations of mutations, but at this point in time, it is still an identifying and learning process.