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	McMahon, F. J.,2001 PMID: 11695948
Citation	McMahon, F. J., S. G. Simpson, et al. (2001). "Linkage of bipolar disorder to chromosome 18q and the validity of bipolar II disorder." Arch Gen Psychiatry 58(11): 1025-1031.
Disease Type	Bipolar II Disorder
Study Design	affected sib pairs
Study Type	Candidate-region linkage study
Sample Size	28 families (n = 247)
SNP/Region/Marker Size	32 markers on 18q21-23
Predominant Ethnicity
Population	American

Detail Info

Sample Diagnosis	RDC
Sample Status	We subsequently tested the findings from set A in the second independent set B. Data for set A were originally reported elsewhere.Briefly, it consisted of 286 diagnosed subjects in 28 families. Of these, 59 subjects (21%) had BPI, 49 subjects (17%) had BPII (plus recurrent major depression), and 28 subjects (10%) had recurrent major depression (RUP). A bestestimate diagnosis of 'phenotype uncertain' was assigned to 69 subjects (24%), and 81 subjects (28%) were considered unaffected. Based on informativeness for linkage analysis, 247 subjects were selected for genotyping. Set B was also originally described elsewhere.It consisted of 30 families, and was completed after set A, but before August 1, 1996 (when the data set was 'frozen' for analysis upon meeting prior thresholds for statistical power).Of the 300 subjects to whom a best-estimate diagnosis could be assigned, 59 (20%) had BPI, 40 (13%) had BPII plus recurrent major depression, 42 (14%) had RUP, and 6 (2%) had schizoaffective manic disorder. Of the remaining subjects, 70 (23%) were considered unaffected, and 83 (28%) were considered 'phenotype uncertain.' The 259 most informative subjects were selected for genotyping.
Replication Size	30 families (n = 259)
Technique	genotyping
Statistical Method	Linkage analysis was performed using the sib_ibd and sib_phase programs in ASPEX.
Result Summary	In exploratory analyses, paternal allele sharing on 18q21 was significantly (P =.03) associated with a diagnostic subtype, and was greatest in pairs where both siblings had bipolar II disorder (BPII). Prospective analysis confirmed the finding that BPII-BPII sibling pairs showed significantly (P =.016) greater paternal allele sharing. Paternal allele sharing across 18q21-23 was also significantly greater in families with at least one BPII-BPII sibling pair. In these families, multipoint affected sibling-pair linkage analysis produced a peak paternal lod score of 4.67 (1-lod confidence interval, 12 centimorgans [cM]) vs 1.53 (1-lod confidence interval, 44 cM) in all families.

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