Editing Hemoglobinopathy (section)

== Combination hemoglobinopathies ==
A combination hemoglobinopathy occurs when someone inherits two different abnormal hemoglobin genes. If these are different versions of the same gene, one having been inherited from each parent it is an example of [[compound heterozygosity]].

Both alpha- and beta- thalassemia can coexist with other hemoglobinopathies. Combinations involving alpha thalassemia are generally benign.<ref>{{Cite journal |last1=Khatri |first1=Govinda |last2=Sahito |first2=Abdul Moiz |last3=Ansari |first3=Saboor Ahmed |date=2021-12-31 |title=Shared molecular basis, diagnosis, and co-inheritance of alpha and beta thalassemia |journal=Blood Research |language=en |volume=56 |issue=4 |pages=332–333 |doi=10.5045/br.2021.2021128 |pmc=8721464 |pmid=34776416}}</ref><ref>{{Cite journal |last1=Wambua |first1=Sammy |last2=Mwacharo |first2=Jedidah |last3=Uyoga |first3=Sophie |last4=Macharia |first4=Alexander |last5=Williams |first5=Thomas N. |date=2006 |title=Co-inheritance of α+-thalassaemia and sickle trait results in specific effects on haematological parameters |journal=British Journal of Haematology |language=en |volume=133 |issue=2 |pages=206–209 |doi=10.1111/j.1365-2141.2006.06006.x |issn=1365-2141 |pmc=4394356 |pmid=16611313}}</ref>

Some examples of clinically significant combinations involving beta thalassemia include:

* [[Hemoglobin C]]/ beta thalassemia: common in [[Mediterranean]] and [[Ethnic groups of Africa|African]] populations generally results in a moderate form of anemia with splenomegaly.<ref>{{Cite web |date=February 2011 |title=Hemoglobin C |url=https://doh.wa.gov/sites/default/files/legacy/Documents/5220/HbCFactSheet.pdf |website=Washington State Department of Health}}</ref>
* [[Hemoglobin D]]/ beta thalassemia: common in the northwestern parts of [[India]] and [[Pakistan]] ([[Punjab region]]).<ref>{{cite journal |vauthors=Torres Lde S |date=March 2015 |title=Hemoglobin D-Punjab: origin, distribution and laboratory diagnosis |journal=Revista Brasileira de Hematologia e Hemoterapia |volume=37 |issue=2 |pages=120–126 |doi=10.1016/j.bjhh.2015.02.007 |pmc=4382585 |pmid=25818823}}</ref>

* [[Hemoglobin E#Hemoglobin E/β-thalassaemia|Hemoglobin E/ beta thalassemia]]: common in [[Cambodia]], [[Thailand]], and parts of [[India]], it is clinically similar to β thalassemia major or β thalassemia intermedia.<ref>{{Cite journal |last1=Olivieri |first1=Nancy F. |last2=Muraca |first2=Giulia M. |last3=O’Donnell |first3=Angela |last4=Premawardhena |first4=Anuja |last5=Fisher |first5=Christopher |last6=Weatherall |first6=David J. |date=May 2008 |title=Studies in haemoglobin E beta-thalassaemia |url=https://onlinelibrary.wiley.com/doi/10.1111/j.1365-2141.2008.07126.x |journal=British Journal of Haematology |language=en |volume=141 |issue=3 |pages=388–397 |doi=10.1111/j.1365-2141.2008.07126.x |pmid=18410572 |issn=0007-1048}}</ref>
* [[Sickle cell-beta thalassemia|Hemoglobin S/ beta thalassemia]]: common in [[Ethnic groups of Africa|African]] and [[Mediterranean]] populations, it is clinically similar to [[sickle-cell anemia]].<ref name=":0">{{Cite web |last=Gerber |first=Gloria F. |date=April 2024 |title=Hemoglobin S–Beta-Thalassemia Disease - Hematology and Oncology |url=https://www.msdmanuals.com/professional/hematology-and-oncology/anemias-caused-by-hemolysis/hemoglobin-s-beta-thalassemia-disease |access-date=2024-12-24 |website=MSD Manual Professional Edition |language=en}}</ref>
* [[Delta-beta thalassemia]] is a rare form of thalassemia in which there is a reduced production of both the delta and beta globins. It is generally asymptomatic.<ref>{{cite book |last1=Pal |first1=G. K. & |url=https://books.google.com/books?id=XpUAihQ7Ib4C&q=microcytosis+definition&pg=PA53 |title=Textbook Of Practical Physiology - 2Nd Edn. |date=2005 |publisher=Orient Blackswan |isbn=9788125029045 |page=53 |language=en |accessdate=17 September 2016}}</ref>

There are two clinically significant combinations involving the sickle cell gene:

* [[Sickle cell-beta thalassemia|Hemoglobin S/ beta thalassemia]]: (see above).<ref name=":0" />
* Hemoglobin S/ hemoglobin C ([[Hemoglobin C|Hemoglobin SC]] disease) occurs when an individual inherits one gene for hemoglobin S (sickle cell) and one gene for hemoglobin C, The symptoms are very similar to sickle cell disease.<ref>{{Cite web |last=Pitone |first=Melanie L. |title=Hemobglobin SC Disease (for Parents) |url=https://kidshealth.org/en/parents/hbsc-disease.html |access-date=2024-12-24 |website=Nemours Foundation |language=english}}</ref>