Ulf Drugge

Familial Amyloidotic Polyneuropathy in Sweden: Geographical Distribution, Age of Onset, and Prevalence

Familial amyloidotic polyneuropathy (FAP) in Swedish patients is associated with the same transthyretin mutation (TTRMet30) as in Portuguese, Japanese, Brazilian and Majorcan patients. Yet, the age of onset of FAP is much later in Sweden than in other populations. We have studied 239 cases of FAP from northern Sweden, their geographical distribution, differences in age of onset, and estimated prevalence and incidence rates. Cases and families concentrate mainly in two areas, around the towns of Skellefteå and Piteå. Mean age of onset was found to be later in the Piteå (58.8 +/- 10.8) than in the Skellefteå area (54.4 +/- 13.5). Unusually high figures were found for prevalence rates (91 x 10(-5) and 104 x 10(-5), respectively) in 1985. Mean yearly incidences were 3.1 x 10(-5) and 4.4 x 10(-5), respectively, over the period 1985-1989.

Vitreous involvement in familial amyloidotic neuropathy a genealogical and genetic study

Extended genealogical studies stretching back to the 17th century were performed concerning the heredity patterns of vitreous involvement in Swedish patients with familial amyloidotic polyneuropathy (FAP). FAP is an autosomal dominant inherited disorder, characterized by extracellular deposition of amyloid and a clinical syndrome of peripheral and autonomic neuropathy. In addition, some patients show typical vitreous opacities. All patients had their origin in a restricted geographical area. Some main patterns arose from this study: 1) Patients who had vitreous opacities as the first symptom of FAP seem to form a separate group, with a distinct age of onset distribution; 2) The familial occurrence of vitreous opacities raises the possibility that other familial factors modify the expression of the FAP gene; 3) The mean age of onset for vitreous opacities is lower for homozygous than for heterozygous patients.

Homozygosity for the transthyretin-Met30-gene in seven individuals with familial amyloidosis with polyneuropathy detected by restriction enzyme analysis of amplified genomic DNA sequences

Holmgren G, Bergström S, Drugge U, Lundgren E, Nording‐Sikström C, Sandgren O, Steen L. Homozygosity for the transthyretin‐Met30‐gene in seven individuals with familial amyloidosis with polyneuropathy detected by restriction enzyme analysis of amplified genomic DNA sequences. Clin Genet 1992:41:39–41.

The gene for familial dystonia with myoclonic jerks responsive to alcohol is not located on the distal end of 9q.

A gene (DYT1) for susceptibility to early‐onset torsion dystonia in Ashkenazi Jewish and Gentile kindreds is situated on chromosome 9q32‐q34 in a 6–7 cM span between markers AK1 and ASS. To determine whether transmission of familial dystonia with myoclonic jerks responsive to alcohol was consistent with a gene in this region, we studied the 37 members of a Swedish family, of whom 20 were so affected. A lod score of < −2.00 from a two‐point linkage analysis with six DNA markers covering a 30 cM span from D9S26 to D9S10 that included the region of the DYT gene indicated that this gene is not located in this region, and that two or more autosomal loci are responsible for hereditary dystonia in humans.

Geographical distribution of haplotypes in Swedish families with Huntington's disease.

This study was planned to determine the number of origins of the mutation underlying Huntingtons disease (HD) in Sweden. Haplotypes were constructed for 23 different HD families, using six different polymorphisms [(CCG)n, GT70, 674, BS1, E2 and 4.2], including two within the gene. In addition, extensive genealogical investigations were performed, and the geographical origin of the haplotypes was studied. Ten different haplotypes were observed suggesting multiple origins for the HD mutation in Sweden. Analysis of the two polymorphic markers within the HD gene (the CCG repeat and GT70) indicates that there are at least three origins for the HD mutation in Sweden. One of these haplotypes (7/A) accounts for 89% of the families, suggesting that the majority of the Swedish HD families are related through a single HD mutation of ancient origin. Furthermore, three of the families that were previously considered to be unrelated could be traced to a common ancestor in the 15th century, a finding that is consistent with this hypothesis.

Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLO‐SL): a genealogical study of Swedish families of probable Finnish background

Four Swedish families in northern Sweden with polycystic lipomembranous ostodysplasia (PLO‐SL) were studied genealogically. Historical and genealogical data provided evidence for a Finnish origin. Both parents of two of the families could be traced back to Finnish ancestors, and the other two families had a common origin in a region with a known Finnish influence, but without evidence for Finnish ancestry. PLO‐SL is the first rare monogenic disease with an autosomal recessive inheritance in Sweden with a probable Finnish origin.

Dopamine beta-hydroxylase gene excluded in four subtypes of hereditary dystonia

SummaryThe hereditary dystonias include a clinically heterogeneous group of movement disorders varying in symptoms, age of onset, and drug responsiveness. Dopamine beta-hydroxylase (DBH), the enzyme that converts dopamine to norepinephrine, has been implicated in dystonia because of increased serum levels of DBH in some patients, the influence of catecholaminergic drugs on the human phenotypes, and altered norepinephrine levels in several brain regions in dystonia patients and in genetically dystonic rodents. In addition, markers linked to the dystonia gene in two ethnic groups map close to the DBH locus on human chromosome 9q34. Here we evaluate the inheritance of restriction fragment length polymorphisms near the DBH gene in families with four subtypes of hereditary dystonia: Jewish and non-Jewish, early onset, generalized idiopathic torsion dystonia (ITD); dopa-responsive dystonia; and myoclonic dystonia. In all families, obligate recombination events were observed between the DBH and dystonia genes, thus excluding the DBH gene as the primary defect.

The First Case of Familial Amyloidotic Polyneuropathy (FAP Met30) in the Finnish Population

Finnish hereditary amyloidosis-Meretoja (FAP type 4) is the predominating type of hereditary amyloidosis in the Finnish population, found in more than 200 individuals. We present a Finnish family with familial amyloidotic polyneuropathy (FAP Met30), a type of amyloidosis hitherto not described in the Finnish population. Genealogical tracing back to the 18th century revealed no connections with Swedish FAP families, but introduction from Sweden is the most probable origin of the FAP Met30 gene.