Genetic linkage and bipolar affective disorder: progress and pitfalls.

The history of linkage studies in bipolar affective disorder is a convoluted affair punctuated by upswings and setbacks, hope and skepticism. Advances in genomics and statistical techniques, and the availability of well-characterized clinical samples, have bolstered the search for disease genes, leading to a new crop of findings. Indeed, recent reports of putative loci on chromosomes 18, 21, X, 4, 6, 13 and 15 have rekindled a sense of optimism. The new findings are reviewed and scrutinized, with implications for future research.