Alpha-thalassemia (α-thalassemia, α-thalassaemia) is a form of thalassemia involving the genes HBA1 and HBA2. Alpha-thalassemia is due to impaired production of 1,2,3, or 4 alpha globin chains, leading to a relative excess of beta globin chains. The degree of impairment is based on which clinical phenotype is present (how many chains are affected).


The worldwide distribution of inherited alpha-thalassemia corresponds to areas of malaria exposure, suggesting a protective role for alpha-thalassemia against the more severe manifestations of malaria. Thus, alpha-thalassemia is common in sub-Saharan Africa, the Mediterranean Basin, the Middle East, South Asia, and Southeast Asia, and different genetic subtypes have variable frequencies in each of these areas. The epidemiology of alpha-thalassemia in the US reflects this global distribution pattern. The most common form of alpha(+) thalassemia seen in the US is due to the -alpha(3.7) deletion, a single alpha-globin gene deletion, and is present in approximately 30% of African Americans. However, even in the homozygous state this disorder will result only in a mild microcytic anemia. The more serious clinical disorders of Hb H and Hb Bart hydrops fetalis syndrome, although found throughout the US today, are more common in the Western US and have dramatically increased in prevalence in the past 2 decades due to increased Asian immigration.


It is most commonly inherited in a Mendelian recessive fashion. It is also connected to the deletion of the 16p chromosome.

It can also be acquired, under rare circumstances. Due to the low occurrence of alpha-thalassemia, the disease can be mistaken for iron deficiency anemia.


α thalassemias result in decreased alpha-globin production, therefore fewer alpha-globin chains are produced, resulting in an excess of β chains in adults and excess γ chains in newborns. The excess β chains form unstable tetramers (called Hemoglobin H or HbH of 4 beta chains) which have abnormal oxygen dissociation curves. The excess γ chains form tetramers which are poor carriers of O2 since their affinity for O2 is too high so it is not dissociated in the periphery. Homozygote α0 thalassaemias, where there is lots of γ4 but no α-globins at all (referred to as Hb Barts), often result in still birth.


There are two genetic loci for α globin, and thus four genes in diploid cells. Two genes are maternal in origin and two genes are paternal in origin. The severity of the α thalassemias is correlated with the number of affected α globin genes: the greater, the more severe will be the manifestations of the disease.

When noting the genotype, a "-" indicates an absence of function, and a "α" indications a functional alpha chain. (In contrast to the "βo" and "β+" notation used in beta-thalassemia, in alpha-thalassemia a distinction between absent and reduced function is not usually noted.)



  1. Go for the original. Piracy is an alarming illegal practice in the Philippines. As consumers, the best thing that we could do is to give our sincerest support through buying original CDs and music video recordings of local artists. Nowadays, the web has put more pressure on the music industry since people can easily access songs by means of Pinoy Tv Online Video downloading and file sharing.

  2. "He has learned a big lesson out of that. He became more cautious and has matured a lot as a fighter," says Restituto "Buboy" Fernandez, a Watch Pinoy Tv Shows Live long-time associate and the assistant trainer for Pacquiao.

  3. Duterte has repeatedly warned he may impose martial law, saying military rule could solve many of the Pinoy Tv live Talk Show.

  4. Thanks to Internet technology, the world of advertising has gone to a whole new level. No longer would you need to buy traditional magazines to search for things to buy, look for jobs or to advertise. You can simply check out Online classified ad websites and you can find the information that you need in no time at all. And most of all, most of Pinoy Channel Online Videos classified ad websites do not charge for usage.

  5. Even though mobile analog Pinoy Tv Latest Video Online receivers has been in the marketplace for several years they have not been a big triumph, which may be due to the fact that they do not have any new features over the normal Television. In a far-ahead scenario, the mobile terminal could merge with the remote controller of the television, taking over the interactive parts of television viewing.

  6. Other popular children's programs with educational value alongside the entertainment factor include Thomas the Tank Engine & Friends, Barney and Friends, which deals mainly with personal relationships and self-esteem, and the long-running Blue's Clues, which has a heavy emphasis on counting, colors, shapes, and the alphabet for very young watchers. The Magic School Bus is television with a science twist for a slightly older audience, following the adventures of a science class and their crazy escapades under the direction of Pinoy Tv HD Tube their wacky teacher.

  7. I can’t believe this. A great testimony that i must share to all HERPES SIMPLEX VIRUS patient in the world i never believed that their could be any complete cure for Herpes or any cure for herpes,i saw people’s testimony on blog sites of how dr Ero prepare herbal medicine that cure and brought them back to life again. i had to try it too and you can,t believe that in just few weeks i started using it all my pains stop gradually and i had to leave without the pills the doctor gave to me. Right now i can tell you that few months now i have not had any pain,delay in treatment leads to death. Here is his email:( whatsapp him with +2348073673757 or text/call me 650) 653-8578....

  8. I was diagnosed of Herpes in 2014 and I have tried all possible means to get the cure but all to no avail, until i saw a post in a health forum about a Herbal Doctor(Dr Aloha) who prepares herbal medicine to cure all kind of diseases including Herpes, at first i doubted if it was real but decided to give it a try, when i contacted Dr Aloha through his Email: he guided me and prepared a herbal medicine and sent it to me via courier Delivery service,when i received the package (herbal medicine) He gave me instructions on how to consume it,i started using it as instructed and i stooped getting outbreaks and the sores started vanishing, could you believe i was cured of this deadly virus within 10-14 days of using this REMEDY,couldn't believe the healing at first until i went for a check-up,indeed i was tested negative to HERPES. Contact this great herbal Doctor today via Email: and get cured permanently. or Call/Text: +1(312) 361-5917

  9. Dr. Osagie God will continue to bless you more abundantly, for the good works you are doing in peoples life, I will keep on writng and posting testimonies about you on the Internet, I’m John Homles , I was a HIV patient, I saw a blog on how Dr. Osagie cured someone, I contacted him and also got my healing, kindly email him now on ( OR
    DROSAGIESOULTIONTEMPLE@YAHOO.COM ) or His Whatsapp number: +2347030465649...thank you my great DR

  10. ​i am just using this time to thanks Stella Rams for posting the number of the good man Mr Ero and am thanking Mr Ero also, i don't have any bad pap smear again ,the drugs work like magic ,if anybody want good cure of HPV , i will advice you to text or call me on 270) 693-5854 for more information or you can contact dr on his herbal is the best as far as I'm concerned ,thanks once again.​

  11. As you all know that HIV/AIDs and Cancer are getting stronger and spreading day by day and that we are not responsible for the pains of our loved ones, but it’s our responsibility to help those who are infected with viruses. The only way for us to find peace in this world is to love one another and stand by each other. Am sharing this comment because I was once suffering from HIV for 4 years and Genital Herpes for some months until I got help from Dr. Osojo who helped me with a herbal cure for both Genital Herpes and my 4 years HIV virus. If you also need help, you can also reach him: { } or call him on +234 810 066 3964. You could also use this link, .Having HIV/Aids or Herpes isn’t the end of your life, it’s actually not a death sentence for you, there is a cure and Dr. Osojo can help you with it as he did mine.