Catherine T. Falk

Human Gene for Torsion Dystonia Located on Chromosome 9q32-q34

Torsion dystonia is a movement disorder of unknown etiology characterized by loss of control of voluntary movements appearing as sustained muscle contractions and/or abnormal postures. Dystonic movements can be caused by lesions in the basal ganglia, drugs, or gene defects. Several hereditary forms have been described, most of which have autosomal dominant transmission with variable expressivity. In the Ashkenazi Jewish population the defective gene frequency is about 1/10,000. Here, linkage analysis using polymorphic DNA and protein markers has been used to locate a gene responsible for susceptibility to dystonia in a large, non-Jewish kinship. Affected members of this family have a clinical syndrome similar to that found in the Jewish population. This dystonia gene (ITD1) shows tight linkage with the gene encoding gelsolin, an actin binding protein, and appears by multipoint linkage analysis to lie in the q32-q34 region of chromosome 9 between ABO and D9S26, a region that also contains the locus for dopamine-beta-hydroxylase.

Estimating the Recombination frequency for the PTC-Kell linkage

SummaryTwo data sets are analyzed for linkage between the PTC and Kell blood group loci. The original report of close linkage for these loci was that of Conneally et al. (1976), where the maximum likelihood estimate of Θ was 0.05. These two new data sets give a combined maximum likelihood estimate of

Analysis for possible linkage between the loci for the Waardenburg syndrome and various blood groups and serological traits.

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Risk factors for coronary artery disease and the use of neural networks to predict the presence or absence of high blood pressure

m=f=0.28. Estimating the recombination frequency for the sexes separately gave

Hereditary dystonia musculorum deformans

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Linkage disequilibrium between the FES, D15S127, and BLM loci in Ashkenazi Jews with Bloom syndrome.

m=0.29,