Linkage analysis of putative schizophrenia gene candidate regions on chromosomes 3p, 5q, 6p, 8p, 20p and 22q in a population-based sampled Finnish family set

During the past decade numerous studies have been published describing chromosomal regions potentially linked with schizophrenia. Unfortunately, none of these studies has been able to conclusively identify any specific gene that predisposes to schizophrenia. Typically evidence for linkage is seen on large chromosomal regions, as expected, containing tens or even hundreds of genes. Furthermore, attempts to replicate the findings have rarely been successful leaving a confusion about the existence of predisposing genes for schizophrenia in a particular region of the genome. We have carried out linkage analysis in a set of 62 pedigrees rising from a genetically isolated population of Finland with markers on six chromosomal regions earlier suggested to harbor predisposing genes for schizophrenia, namely 3p,(1) 5q(2,3) 6p,(4) 8p,(1) 20p,(5) and 22q.(6,7) We were not able to find significant evidence for linkage on any of these chromosomal regions. However, some support for linkage was found on all studied chromosomal regions, except 3p.