| Summary: | Chromosome 22q is suspected to harbor risk genes for schizophrenia as well as bipolar affective disorder. This is evidenced through genetic mapping studies, investigations of cytogenetic abnormalities, and direct examination of candidate genes. In a recent study of distantly related patients from the Faroe Islands we have obtained evidence suggesting two regions on chromosome 22q13 to potentially harbor susceptibility genes for both schizophrenia and bipolar affective disorder. We have selected a number of candidate genes from these two regions for further analysis, including the neuro-gene WKL1, in which a missense mutation recently has been suggested to cause catatonic schizophrenia in a German family. The selected candidate genes were analyzed by a combination of database search and direct sequencing in a subset of the patients from the Faroe Islands in order to identify SNPs in the coding regions and in regions possibly affecting expression level and splicing of the genes. For efficient detection of the SNPs identified multiplex PCR and SBE (single base extension) reactions were developed. Subsequently the SNPs were analyzed in the total Faroese sample of distantly related patients and unrelated controls, and in a Scottish case-control sample comprising 200 schizophrenics, 200 bipolar patients and 200 controls. None of the investigated SNPs have so far showed strong evidence of association to either bipolar disorder or schizophrenia.
|
|---|