Based on data from 71 multiplex nuclear families (527 subjects) ascertained through an index case
with a diagnosis of bipolar illness (n=53) or schizophrenia (n=18) we have addressed the question
of diagnosis-independent susceptibility to functional psychoses. Of these subjects, 469 were
genotyped for 553 polymorphisms of a genome scan along with 48 candidate genes which have been
hypothesized to be involved in psychotropic drug response and to lie in genomic regions harboring
vulnerability loci for functional psychoses.
Our search for vulnerability loci included standard multipoint linkage analysis (Allegro) along with
the multivariate genetic vector space method, which allows one to detect oligogenic configurations of
genomic loci and their non-linear interactions. Linkage analyses, carried out separately for the two
populations of families ascertained through an index case with a diagnosis of bipolar illness and
schizophrenia, yielded several genomic regions on chromosomes 1,4,5,6,11 and 22 with striking
similarities between NPL-scores. Important here is the approximate parallelity of the curve
characteristics rather than the absolute size of the scores (Figure).
Most interestingly, there was some overlap between genomic regions identified as being linked to
vulnerability to functional psychoses and those identified through our study on psychotropic drug
response. Multivariate analyses searching for oligogenic configurations of genomic loci that explain
a major proportion of observed phenotypic variance are currently being carried out. First results
indicate contributions of those genomic loci that were previously identified through our
investigation into ethnicity-independent vulnerability to functional psychoses.
Stassen HH, Begleiter H, Porjesz B, Rice J, Scharfetter C, Reich T: Structural decomposition of
genetic diversity in families with alcohol dependence. Genetic Analysis Workshop 11: Analysis
of genetic and environmental factors in common diseases. Genetic Epidemiology 1999; 17:
325-330
Stassen HH and Scharfetter C: Integration of genetic maps by polynomial transformations.
Am J Med Genetics B 2000; 96: 108-113
Stassen HH, Bridler R, Hägele S, Hergersberg M, Mehmann B, Schinzel A, Weisbrod M, Scharfetter C:
Schizophrenia and smoking: evidence for a common neurobiological basis?
Am J Med Genetics B 2000; 96: 173-177
Hoffmann K, Stassen HH, Reis A: Genkartierung in Isolatpopulationen. Medizinische Genetik 2000;
12,4: 428-437
Stassen HH, Scharfetter C: Oligogenic approaches to the predisposition of asthma in ethnically
diverse populations. Genetic Analysis Workshop 12: Analysis of genetic and environmental factors
in common diseases. Genetic Epidemiology 2001; 21(1): 284-289
Stassen HH, Hoffmann K, Scharfetter C: Similarity by state/descent and genetic vector spaces:
Analysis of a longitudinal family study. Genetic Analysis Workshop 13: Analysis of longitudinal
family data for complex diseases and related risk factors. BMC Genet 2003; 4, S59: 1-6
Stassen HH, Bridler R, Hell D, Weisbrod M, Scharfetter C: Ethnicity-independent genetic basis
of functional psychoses. A Genotype-to-phenotype approach. Am J Med Genetics B 2004; 124:
101-112
Berger M, Stassen HH, Köhler K, Krane V, Mönks D, Wanner C, Hoffmann K, Hoffmann MM, Zimmer M,
Bickeböller H, Lindner TH: Hidden population substructures in an apparently homogeneous
population bias association studies. Eur J Hum Genetics 2006; 14: 236-244
Stassen HH, Szegedi A, Scharfetter C: Modeling Activation of Inflammatory Response System.
A Molecular-Genetic Neural Network Analysis. BMC Proceedings 2007, 1 (Suppl 1): S61, 1-6
Stassen HH, Hoffmann K, Scharfetter C: The Difficulties of Reproducing Conventionally Derived
Results through 500k-Chip Technology. BMC Genet Proc. 2009; 3 Suppl 7: S66