Study Report

Basic Info

Reference	Furlong, R. A., 1998 (b) PMID: 9754623
Citation	Furlong, R. A., T. A. Coleman, et al. (1998). "No association of a functional polymorphism in the dopamine D2 receptor promoter region with bipolar or unipolar affective disorders." Am J Med Genet 81(5): 385-387.
Disease Type	Bipolar Disorder & Major Depressive Disorder
Study Design	case-control
Study Type	Candidate-gene association study
Sample Size	One hundred and thirty-one unrelated bipolar patients and 128 unrelated unipolar patients and 262 anonymous unrelated controls
SNP/Region/Marker Size	1 variant
Predominant Ethnicity	Caucasian
Population	East Anglian
Gender	58 male, 73 female with bipolar, 49 male, 79 female with unipolar, 116 male, 146 female controls

Detail Info

Sample Diagnosis	Research Diagnostic Criteria
Sample Status	The patients were assessed by trained clinicians using the SADS-L interview [Endicott and Spitzer, 1978], supplemented by case note review, meeting Research Diagnostic Criteria for bipolar affective disorder I or major depressive disorder [Spitzer et al., 1978]. The inclusion criteria for the unipolar sample comprised an age of onset of the first episode of depression between ages 18-65; at least two episodes of unipolar major depression; and at least one inpatient admission for the treatment of depression.
Technique	PCR amplification and genotyping
Statistical Method	Odds ratios with 95% confidence intervals were calculated using the general loglinear analysis option of the SPSS version 6.0 software package (SPSS, Inc., Chicago, IL).
Result Summary	There were no significant differences in DRD2 allele or genotype frequencies between the affective disorder and control groups. These results do not support a major role for the DRD2 gene in the etiology of either bipolar or unipolar affective disorders.

Genetic factors reported by this study for BD

Other variants reported by this study for BD (count: 1)

Variant Name	Related Gene	Type	Allele Change	Risk Allele	Statistical Values	Author Comments	Result Category
DRD2 -141CIns/Del	DRD2	insertion/deletion			allelic P-value=0.42, X²=0.65, df=1; genotypic P-value=0.09, X²=2.94, df=1; OR (95% CI)=0.83 (0.52-1.31) of allele 2 vs. 1, OR (95% CI)=0.64 (0.38-1.07) of 2 2 vs. 1 2 in bipolar; allelic P-value=0.72, X²=0.13, df=1; genotypic P-value=0.31, X²=1.03, df=1; OR (95% CI)=0.93 (0.63-1.38) of allele 2 vs. 1, OR (95% CI)=0.80 (0.51-1.24) of 2 2 vs. 1 2 in the combined sample	No significant association with this polymorphism was found ...... No significant association with this polymorphism was found in either disorder, not even when both groups were combined to give an 'affective disorder' group. More...	Negative

Genes reported by this study for BD (count: 1)

Gene	Statistical Values/Author Comments	Result Category
DRD2	These results do not support a major role for the DRD2 gene in the etiology of either bipolar or uni...... These results do not support a major role for the DRD2 gene in the etiology of either bipolar or unipolar affective disorders. More...	Negative

Genetic factors reported by this study for SZ and/or MDD

Other variants reported by this study for SZ/MDD

Disease	Variant Name	Related Gene	Type	Statistical Values	Description	Result Category
MDD	DRD2 -141CIns/Del	DRD2	insertion/deletion	allelic P-value=0.82, X²=0.06, df=1; genotypic P-value=0.91, X²=0.01, df=1; OR (95% CI)=1.06 (0.64-1.75) of allele 2 vs. 1, OR (95% CI)=1.03 (0.58-1.83) of 2 2 vs. 1 2 in bipolar; allelic P-value=0.72, X²=0.13, df=1; genotypic P-value=0.31, X²=1.03, df=1; OR (95% CI)=0.93 (0.63-1.38) of allele 2 vs. 1, OR (95% CI)=0.80 (0.51-1.24) of 2 2 vs. 1 2 in the combined sample	No significant association with this polymorphism was found in either disorder, not even when both groups were combined to give an 'affective disorder' group.	Negative

Genes reported by this study for SZ/MDD

Disease	Gene	Description	Result Category
MDD	DRD2	These results do not support a major role for the DRD2 gene in the etiology of either bipolar or unipolar affective disorders.	Negative