Editing Iron overload (section)

===Viking hypothesis===
Studies and surveys conducted to determine the frequencies of hemochromatosis help explain how the mutation migrated around the globe. In theory, the disease initially evolved from travelers migrating from the north. Surveys show a particular distribution pattern with large clusters and frequencies of gene mutations along the western European coastline.<ref>{{Cite web|url=http://www.hematology.org/Thehematologist/Diffusion/6103.aspx|title=Clinical Penetrance of HFE Hereditary Hemochromatosis, Serum Ferritin Levels, and Screening Implications: Can We Iron This Out?|date=2008-05-01|website=www.hematology.org|access-date=2018-04-11|archive-date=2018-06-15|archive-url=https://web.archive.org/web/20180615135540/http://www.hematology.org/Thehematologist/Diffusion/6103.aspx|url-status=dead}}</ref> This led the development of the "[[Viking]] Hypothesis".<ref>{{Cite journal|last1=Symonette|first1=Caitlin J|last2=Adams|first2=Paul C|date=June 2011|title=Do all hemochromatosis patients have the same origin? A pilot study of mitochondrial DNA and Y-DNA|journal=Canadian Journal of Gastroenterology|volume=25|issue=6|pages=324–326|issn=0835-7900|pmc=3142605|pmid=21766093|doi=10.1155/2011/463810|doi-access=free}}
</ref> Cluster locations and mapped patterns of this mutation correlate closely to the locations of [[Viking expansion|Viking settlements in Europe]] established c.700 AD to c.1100 AD. The Vikings originally came from Norway, Sweden and Denmark. [[Viking ships]] made their way along the coastline of Europe in search of trade, riches, and land. Genetic studies suggest that the extremely high frequency patterns in some European countries are the result of migrations of Vikings and later [[Normans]], indicating a genetic link between hereditary hemochromatosis and Viking ancestry.<ref name=":2">{{Cite web|url=https://www.toomuchiron.ca/video/|title=Videos: Hereditary Hemochromatosis {{!}} Canadian Hemochromatosis Society|website=www.toomuchiron.ca|access-date=2018-04-11|archive-date=2018-04-11|archive-url=https://web.archive.org/web/20180411174723/https://www.toomuchiron.ca/video/|url-status=dead}}</ref>