Evidence for association of an ACCN1 gene variant with response to lithium treatment in Sardinian patients with bipolar disorder.

Aims: Bipolar disorder (BD) is a lifelong psychiatric illness characterized by manic and depressive episodes affecting 1–5% of the general population. Among mood-stabilizing treatments, lithium represents the mainstay in the therapeutic management of BD. However, besides the relatively high rate of excellent responders, a significant fraction of patients present patterns of partial or nonresponse to lithium. This variability might be influenced by genetic factors, even though findings have so far been inconclusive. Here, we present the results of an exploratory genome-wide scan followed by extended genotyping carried out on a sample of 204 Sardinian BD patients characterized for lithium response. Materials & methods: Phenotypic assessment of lithium response was made using the retrospective criteria of long-term treatment response scale. Using Affymetrix® 6.0 SNP arrays, we genotyped a subsample of 52 BD patients evenly distributed at the extreme ends of the treatment response scale. The associated SNPs w...