Study Report

Reference	Karege, F.,2010 PMID: 20214684
Citation	Karege, F., N. Perroud, et al. (2010). "Association of AKT1 gene variants and protein expression in both schizophrenia and bipolar disorder." Genes Brain Behav 9(5): 503-511.
Disease Type	Bipolar Disorder & Schizophrenia
Study Design	case-control
Study Type	Candidate-gene association study
Sample Size	384 unrelated SCZ patients, 130 unrelated BPD patients and 165 unrelated healthy controls (HCT).
SNP/Region/Marker Size	6 SNPs
Predominant Ethnicity	Caucasian
Population	Swiss and French
Gender	Female distribution was 45%, 48% and 39%, respectively, for SCZ, BPD and HCT.
Age Group	Adults : Mean age(SD) was 35(5), 41(11) and 44(13) years respectively, for SCZ, BPD and HCT.

Sample Diagnosis	DSM
Sample Status	All subjects were of West European origin. Patients were recruited from Switzerland (Geneva and Lausanne Hospitals) and France (University affiliated department of Creteil University). Controls were recruited from the Blood Donor Centre of the University Hospital of Geneva. Subjects were assessed by trained psychiatrists for psychiatric diagnoses using either the French version of the Diagnostic Interview for Genetics Studies (DIGS) or theMini International Neuropsychiatric Interview (MINI) (Nurnberger et al . 1994; Preisig et al . 1999; Sheehan et al . 1998).
Technique	genotyping
Statistical Method	Logistic regression under an additive genetic model adjusted by age and gender was used to investigate the association between genotypes and diagnoses (SCZ vs. controls, BPD vs. controls and all cases vs. controls).Haplotype analyses were conducted using logistic regression adjusted by the same covariates.
Result Summary	Of the 39 SNPs that are suitable for linkage disequilibrium (LD) studies, 14 have been analyzed by allele-specific PCR in a sample of 50 parent-proband triads with bipolar disorder. A haplotyped marker comprised of five SNPs, spanning the region between exon 9 and exon 15, was constructed for each individual, and transmission/disequilibrium test (TDT) analysis revealed this haplotype to be in linkage disequilibrium with bipolar disorder (allele-wise TDT p = 0.001, genotype-wise TDT p = 0.0004). These data replicate our previous finding of linkage to markers within and near DAT in a largely different family set, and provide further evidence for a role of DAT in bipolar disorder.