Linkage analyses of candidate chromosomal regions in bipolar disorder complex pedigrees

Objective To explore the genetic susceptibility of bipolar disorder. Methods Seven multiplex bipolar disorder pedigrees were collected. Thirty microsatellite markers in 4p,4q, 12q, 13q,21q,22q were evaluated initially and 12 additional markers were genotyped for fine scan between a domain of about 20 cM in 21q22, which had got a suggestive linkage in step one. Linkage analyses were carried out by GENEHUNTER 2. 1 software. Results Evidence for linkage was found at D21S263, D21S1252 and D22S423 with NPL score of 1.64, 1.41 and 1.40. By fine scan and linkage analyses, we got NPL scores of 1.44, 1.52, 1.54 and 1.89 with score pairs and score all at D21S262 and D21S1920 respectively. Conclusions Loci in 21q22.11-13 and 22q13.1 may contribute to bipolar disorder susceptibility in this sample. Key words: Bipolar disorder;  Genome;  Linkage (Genetics)