Editing Hemoglobinopathy (section)

==Hemoglobin functions==
Hemoglobin is a [[protein]] containing [[ferrous|iron]] that facilitates the transportation of [[oxygen]] in [[Red blood cell|red blood cells]].<ref>{{cite book |last1=Maton |first1=Anthea |url=https://archive.org/details/humanbiologyheal00scho |title=Human Biology and Health |author2=Jean Hopkins |author3=Charles William McLaughlin |author4=Susan Johnson |author5=Maryanna Quon Warner |author6=David LaHart |author7=Jill D. Wright |publisher=Prentice Hall |year=1993 |isbn=978-0-13-981176-0 |location=Englewood Cliffs, New Jersey, US}}</ref> Hemoglobin in the [[blood]] carries oxygen from the [[Lung|lungs]] to the other tissues of the body, where it releases the oxygen to enable [[aerobic respiration]] which powers the [[metabolism]]. Normal levels of hemoglobin vary according to sex and age in the range 9.5 to 17.2 grams of hemoglobin in every deciliter of blood.<ref>{{Cite web |title=Hemoglobin: MedlinePlus Medical Encyclopedia |url=https://medlineplus.gov/ency/article/003645.htm |access-date=2025-01-02 |website=medlineplus.gov |language=en}}</ref>

Hemoglobin also transports other gases. It carries off some of the body's respiratory [[carbon dioxide]] (about 20–25% of the total)<ref>{{cite book |last=Patton |first=Kevin T. |url=https://books.google.com/books?id=Ko2bBgAAQBAJ |title=Anatomy and Physiology |date=2015-02-10 |publisher=Elsevier Health Sciences |isbn=978-0-323-31687-3 |access-date=2016-01-09 |archive-url=https://web.archive.org/web/20160426205246/https://books.google.com/books?id=Ko2bBgAAQBAJ |archive-date=2016-04-26 |url-status=live}}</ref> as [[carbaminohemoglobin]], in which CO<sub>2</sub> binds to the [[heme protein]]. The molecule also carries the important regulatory molecule [[nitric oxide]] bound to a [[thiol]] group in the globin protein, releasing it at the same time as oxygen.<ref name="Epstein-1998">{{cite journal |last1=Epstein |first1=F. H. |last2=Hsia |first2=C. C. W. |year=1998 |title=Respiratory Function of Hemoglobin |journal=New England Journal of Medicine |volume=338 |issue=4 |pages=239–47 |doi=10.1056/NEJM199801223380407 |pmid=9435331}}</ref>