For over 2000 years Jews have been a migratory people establishing communities throughout the Middle East and Mediterranean basin. Contemporary Jewish populations can be divided into three groups according to their area of long-term residence: Middle Eastern (or Oriental) Jews, Sephardi Jews, and Ashkenazi Jews.
From the 6th to 9th century, some Jews migrated from the Middle East west to Germany, France and England. In the 12th and 13th centuries, these Jews were expelled from Western Europe and moved east, settling largely in Poland, Lithuania, Belarus, the Ukraine and Russia, where they remained, largely isolated, for the following five centuries.
In the late 19th and early 20th centuries, this population, now referred to as Ashkenazi Jewry, moved westwards with large migrations to the Americas, Western Europe, Australia and South Africa and some returning to the area which is now modern Israel.
In Britain, it is estimated that 90% - 95% of Jewish people are of Ashkenazi Jewish ancestry.
Having been reproductively isolated for centuries – and having grown from a small number of founders into a large population in a fairly short period – Ashkenazi Jews are a relatively homogenous group that have inherited a range of rare genetic disorders.
For over 50 years, much research has focused on identifying genetic disorders among people of Ashkenazi descent. More than 20 disorders have been established as being of particular relevance to this group. Though rare, many are serious, debilitating and life-shortening.
The link below provides a summary of some genetic disorders that are particularly relevant to people of Ashkenazi ancestry.
Other disorders established as being of higher prevalence among Ashkenazi Jews include: non-syndromic hearing loss and maple syrup urine disease.
For more information about each of these disorders, please click on the relevant disorder page within the Ashkenazi Disorders section on the left of this page.
PLEASE NOTE: These disorder pages are provided for information and educational purposes only and do NOT represent advice regarding individual medical cases. If you have personal concerns about being affected by any of these disorders, we recommend that you consult with your doctor or another relevant healthcare specialist.