ASPARTYLGLUCOSAMINURIA IN NORTHERN NORWAY - A MOLECULAR AND GENEALOGICAL STUDY

Aspartylglucosaminuria (AGU, McKusick 208400) is an autosomal recessiv e lysosomal storage disorder. Ninety percent of all patients are from Finland and only sporadic cases have been reported from elsewhere. In northern Norway, however, nine patients from seven families have been diagnosed with AGU. All these Norwegian patients were homozygous for t he most prevalent Finnish AGU mutation (AGU(Fin)) and show the polymor phism uniquely associated with AGU(Fin) in Finland. Genealogical inves tigation of nine parents proved Finnish ancestry in all pedigrees. The refore, AGU in Norway most likely resulted from immigration of Finnish carriers. These Finnish immigrants originated mostly from the Tornio valley area in northern Finland in a continuous immigration movement f rom 1700 to 1900. The majority settled in the western part of northern Norway, leading to a ''cluster'' of AGU in that particular area. The Finnish immigrants. intermixed considerably with Lapps and these two e thnic origins should thus be considered as high risk groups for AGU(Fi n) in northern Norway.