BDgene

Core Gene from Gene Prioritization Pathways from PBA (Pathway-based Analysis) Enriched Pathways for Core Genes Enriched Pathways for Cross-disorder Genes

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Basic Info

Reference	Green, E. K., 2006 PMID: 16388065
Citation	Green, E. K., R. Raybould, et al. (2006). "Genetic variation of brain-derived neurotrophic factor (BDNF) in bipolar disorder: case-control study of over 3000 individuals from the UK." Br J Psychiatry 188: 21-25.
Disease Type	Bipolar Disorder
Study Design	case-control
Study Type	Candidate-gene association study
Sample Size	864 patients with bipolar I disorder, 98 patients with bipolar II disorder and 2100 controls
SNP/Region/Marker Size	1 SNP
Predominant Ethnicity	Caucasian
Population	British
Gender	37% male patients with bipolar I disorder, 39% male patients with bipolar II disorder, 47% male controls
Age Group	adults : mean age=48 years (s.d.=13) for bipolar I disorder, mean age=52 years (s.d.=13) for bipolar II disorder, mean age=42.2 years (s.d.=11.2) for controls

Detail Info

Sample Diagnosis	DSM-IV
Sample Status	Individuals were recruited through mental health services in England and Wales and met DSM-IV (American Psychiatric Association, 1994) criteria for bipolar I disorder (n=864) or bipolar II disorder (n=98). Their sample of people with bipolar disorder had a lifetime occurrence of one or more psychotic features in 56% of those with bipolar I disorder and 18% of those with bipolar II disorder. Other key clinical variables were rated according to written operational guidelines in use by our group and available on request from the authors. These included age at onset of impairment by illness (those with bipolar I disorder, mean age at onset=26 years (s.d.=10); those with bipolar II disorder, mean age at onset=30 years (s.d.=13)), family history of psychiatric illness (history of psychiatric illness in first- or second-degree relative: those with bipolar I disorder 71%; those with bipolar II disorder, 76%), definite lifetime occurrence of rapid cycling (defined as at least one period of 12 months during which four or more distinct episodes of major mood disorder occurred; present in 13% of those with bipolar I and 18% of those with bipolar II disorder) and definite lifetime occurrence of postpartum triggering of psychotic major affective episodes (present in 14% of those with bipolar I and 3% those with bipolar II disorder).
Technique	genotyping using a fluorescence polarisation primer extension assay, using the AcycloPrime Kit
Statistical Method	Tests for differences between allele and genotype frequencies were performed using Pearson chi-square analysis of contingency tables. Two-tailed P values are reported. Adjustment for multiple testing was made using Bonferroni correction.
Result Summary	They found no overall evidence of allele or genotype association. However, they found association with disease status in the subset of 131 individuals that had experienced rapid cycling at some time (P=0.004). They found a similar association on re-analysis of their previously reported family-based association sample (P<0.03, one-tailed test). Variation at the Val66Met polymorphism of BDNF does not play a major role in influencing susceptibility to bipolar disorder as a whole, but is associated with susceptibility to the rapid cycling subset of the disorder.

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
BDNF Val66Met	BDNF	point mutation	Val/Met		allelic P-value = 0.39, X²=0.73, df=1, OR (95% CI)=1.07 (0.92-1.22), genotypic P-value = 0.68, X²=0.77, df=2 for Bipolar I and II disorder; allelic P-value = 0.36, X²=0.83, df=1, OR (95% CI)=1.07 (0.93-1.24), genotypic P-value = 0.64, X²=0.89, df=2 for Bipolar I disorder; allelic P-value = 0.98, X²=0.00, df=1, OR (95% CI)=1.00 (0.70-1.45), genotypic P-value = 0.96, X²=0.09, df=2 for Bipolar II disorder; allelic P-value = 0.0040, X²=8.28, df=1, OR (95% CI)=1.74 (1.19-2.56), genotypic P-value = 0.015, X²=8.47, df=2 for rapid-cycling bipolar disorder; re-analysis P-value < 0.03, one-tailed test	No differences in allele or genotype frequencies were seen b...... No differences in allele or genotype frequencies were seen between cases and controls for any of the diagnostic groups. However, we found association with disease status in the subset of rapid cycling. We found a similar association on re-analysis of the previously reported family-based association sample. More...	Positive

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