Study Report

Reference	Macintyre, D. J.,2010 PMID: 20371266
Citation	Macintyre, D. J., K. A. McGhee, et al. (2010). "Association of GPR50, an X-linked orphan G protein-coupled receptor, and affective disorder in an independent sample of the Scottish population." Neurosci Lett 475(3): 169-173.
Disease Type	Bipolar Disorder & Major Depressive Disorder
Study Design	case-control
Study Type	Candidate-gene association study
Sample Size	338 patients with BD, 359 patients with major depressive disorder (MDD) and 913 control individuals
SNP/Region/Marker Size	6 variants
Predominant Ethnicity	Caucasian
Population	Scottish
Gender	BD patients(145 male, and 193 female),MDD patients (144 male and 215 female) and controls(620 male and 293 female)

Sample Diagnosis	DSM
Sample Status	We recruited out-patients attending general psychiatry clinics in the East of Scotland, from the same population as in the initial study . Participants were eligible if they fulfilled DSM-IV criteria for MDD or BD. Subjects with a history of head injury or a primary diagnosis of personality disorder were excluded. The project was conducted in accordance with the Declaration of Helsinki. Three hundred and thirty-eight subjects with BD and 359 with MDD were recruited. Of those patients with MDD, a currently depressed early onset subset (n = 56, of which 19 were male and 37 female) were recruited (by DM) from the psychiatry clinic serving the University Health Centre, which provides primary medical care for over 90% of students at the University of Edinburgh. Control samples were obtained in the following manner: eight hundred and eighty-four unscreened (population) blood samples were obtained from the Scottish Blood Transfusion Service and from general practises in the East of Scotland. Twenty-nine friends of the university health subjects volunteered to act as controls. They were screened for psychiatric disorder using the Structured Clinical Interview for DSM-IV-TR (SCID), and underwent detailed phenotyping, as described below.
Technique	PCR and sequencing
Statistical Method	Case-control association analyses were performed using X2 goodness of fit test (Haploview v4.1; [4]) for single markers and BD, MDD and subgroup. 100,000 permutations were used to correct for multiple testing.
Result Summary	Three alleles were detected: STin2.9, STin2.10 and STin2.12. None of the three diagnostic samples showed preferential transmission of alleles that reached conventional levels of statistical significance. We could not confirm previous results that STin2.12 allele increases susceptibility to bipolar disorder type I. The rare STin2.9 showed a non-significant trend for preferential transmission in the sample as a whole: 18 transmitted versus 11 non-transmitted (P = 0.2). The VNTR polymorphism in the 5-HTT gene does not appear to be a major risk factor for increasing susceptibility to major psychiatric disorders.