GAUCHER DISEASE (NORRBOTTNIAN TYPE-III) - PROBABLE FOUNDERS IDENTIFIED BY GENEALOGICAL AND MOLECULAR STUDIES

Gaucher disease type III (GD) is found at a high frequency in northern Sweden. The contemporary Swedish index families are found in two geog raphically distinct clusters with the highest world-wide frequency of type III GD. A single T-to-C transition in exon 10 has previously been identified in patients from one of the two isolates and we report the re the same mutation in the second isolate. Mutational analysis was co mbined with a genealogical reconstruction of 19 contemporary index fam ilies. Both clusters were traced back to two corresponding pairs of an cestors over a 9-13 generation span. Molecular studies show that the t wo clusters are compatible with a single founder who arrived in northe rn Sweden in or before the 16th century.