Introduction

Hemochromatosis has a distinctive distribution that reflects the movements of people of northwestern Europe during historic times. The ‘major’ hemochromatosis gene in northern Europeans is linked to the HLA gene locus, and occurs with greatest frequency among the populations of the countries that surround the North Sea. These countries include Norway, Denmark, Iceland, western and southern Germany, the United Kingdom, Ireland, and France (particularly in the Brittany peninsula) (Fig. 4.1; Table 4.1). Within Sweden, there is considerable variation in prevalence of hemochromatosis from one area to another. The gene frequency appears to be lower in southern Italy and in western Russia. Hemochromatosis occurs in Portugal Spain, Estonia, Hungary, and northern Italy, but more data are needed to clarify the prevalence and the gene frequency in these countries. Hemochromatosis is rare in Finland, Greece, Turkey, North Africa and Asia. The prevalence of hemochromatosis has not been ascertained in most of eastern Europe. Frequency of the hemochromatosis gene is low in Ashkenazic Jews. In countries that have large populations derived principally from the North Sea littoral, including Canada, the United States, South Africa, Australia and New Zealand, the prevalence of hemochromatosis mirrors that of the parent populations of Europe.

Source of the hemochromatosis mutations

The striking geographic distribution of hemochromatosis has led to the conjecture that hemochromatosis is the result of a relatively recent mutation (one that has occurred in hundreds of generations) that occurred in a Celtic population.