0000000000077239
AUTHOR
Max P. Baur
Family studies in scleroderma (systemic sclerosis) demonstrating an HLA-linked increased chromosomal breakage rate in cultured lymphocytes
An increased chromosomal breakage rate (ICBR) was found in 27 of 28 patients with scleroderma (systemic sclerosis, SS) - 5 with the syndrome including calcinosis cutis, Raynaud phenomenon, esophagus hypomotility, sclerodactyly and telangiectasia (CREST), 4 incomplete CREST, 1 overlapping syndrome, 18 progressive systemic sclerosis (PSS). Not only the patients, but also about half of their first-degree relatives showed an increased chromosomal breakage rate (more than 5 breaks per 100 metaphases). This character segregated as a dominant marker in nine families of scleroderma patients. In the six informative of the nine families, the ICBR trait showed close linkage with the HLA region on chro…
A genome screen for genes predisposing to bipolar affective disorder detects a new susceptibility locus on 8q
Bipolar affective disorder (BPAD), also known as manic depressive illness, is a severe psychiatric disorder characterized by episodes of mania and depression. It has a lifetime prevalence of approximately 1% in all human populations. In order to identify chromosomal regions containing genes that play a role in determining susceptibility to this psychiatric condition, we have conducted a complete genome screen with 382 markers (average marker spacing of 9.3 cM) in a sample of 75 BPAD families which were recruited through an explicit ascertainment scheme. Pedigrees were of German, Israeli and Italian origin, respectively. Parametric and non-parametric linkage analysis was performed. The highe…
Evaluation of linkage of bipolar affective disorder to chromosome 18 in a sample of 57 German families.
Previously reported linkage of bipolar affective disorder to DNA markers on chromosome 18 was reexamined in a large sample of German bipolar families. Twenty-three short tandem repeat markers were investigated in 57 families containing 103 individuals with bipolar I disorder (BPI), 26 with bipolar II disorder (BPII), nine with schizoaffective disorder of the bipolar type (SA/BP), and 38 individuals with recurrent unipolar depression (UPR). Evidence for linkage was tested with parametric and non-parametric methods under two definitions of the affected phenotype. Analysis of all 57 families revealed no robust evidence for linkage. Following previous reports we performed separate analyses afte…
Comparison of Different Methods for the Calculation of Indices of Paternity
The qualitative decision about paternity in trio cases on the basis of DNA multilocus profiles is no problem. If there are more than 1 or 2 exclusion patterns (band present in child, which is neither present in mother or alleged father), the putative father has to be excluded. The problems arise, if, in the case of a non exclusion, one wants to quantify the evidence for paternity. Different statistics have been proposed for this purpose. This paper discusses three of these statistics and demonstrates their application to real data.
A possible susceptibility locus for bipolar affective disorder in chromosomal region 10q25--q26.
In an attempt to identify susceptibility loci for bipolar affective disorder, we are currently conducting a systematic genome screen with highly polymorphic microsatellite markers at an average marker spacing of 10 cM in a series of 75 families, comprising 66 families from Germany, eight families from Israel, and one family from Italy. The families were ascertained through index cases with bipolar affective disorder. The distribution of diagnoses is as follows: 126 individuals with bipolar I disorder, 40 with bipolar II disorder, 14 with schizoaffective disorder of the bipolar type, 40 individuals with recurrent unipolar depression, 51 with a minor psychiatric diagnosis, and two individuals…
Likelihood Calculations in Paternity Testing on the Basis of DNA-Fingerprints
DNA-fingerprints seem to be a powerful tool in paternity testing. But the quantification of the results in terms of likelihood and likelihood ratios is a problem, because in most cases the correct genetic model and its parameters are not known. Two approaches have been suggested to circumvent these problems. The use of band sharing rates to distinguish between pairs of relatives and pairs of unrelated individuals, and the calculation of likelihood ratios on the basis of simplifying assumptions. The first approach reduces the available genetic evidence to “phenotypic” similarities. The second one makes unjustified simplifying assumptions. These two decision strategies have to be examined wit…
Genetic analysis of IDDM: The GAW5 multiplex family dataset
In a collaborative effort by 12 centers from Europe and North America, data were assembled from 94 multiplex families with insulin-dependent diabetes mellitus (IDDM) for analysis of genetic and other factors of possible etiological importance. The dataset contains information on the following genetic markers: HLA-DR beta and -DQ beta restriction fragment length polymorphisms (RFLPs), three RFLPs detected with two probes that map 5' to the insulin gene, the serologically defined HLA loci, and the immunoglobulin allotypes. Data also were included for auto-antibodies to insulin and pancreatic islet cells as possible indicators of pathogenesis and for antibodies to certain viruses that have bee…