Table S1. Population- and family-based association studies of bipolar disorder and the BDNF Val66Met polymorphism

Study / Study Design a / Ethnicity / Diagnostic Criteria b / Number of Cases/Controls or Families / Val Allele Frequency c / Odds Ratio (95% CI) d / P valuee
European/European descent:
Sklar 2002 / FAM / USA (Hopkins) / RDC / 136 / 0.83 / 1.56 (1.01-2.40) / 0.042
Sklar 2002* / FAM / USA (NIMH) / RDC / 189 / 0.80 / 1.27 (0.89-1.81) / 0.18
Sklar 2002 / FAM / British Caucasian / DSM-IV / 145 / 0.83 / 1.19 (0.74-1.90) / 0.47
Geller 2004 / FAM / USA / DSM-IV / 53 / 0.79 / 2.33 (1.07-5.09) / 0.014
Oswald 2004 / CC / Belgian / DSM-IV / 108/158 / 0.79 / 0.89 (0.59-1.35) / 0.94
Skibinska 2004 / CC / Polish / DSM-IV / 352/375 / 0.82 / 1.13 (0.86-1.49) / 0.41
Lohoff 2005* / CC / USA / DSM-IV / 621/998 / 0.79 / 1.22 (1.02-1.47) / 0.028
Neves-Pereira 2005 / CC / Scottish / DSM-IV / 263/350 / 0.78 / 1.07 (0.81-1.41) / 0.54
Schumacher 2005 / CC / German / DSM-IV / 281/1097 / 0.81 / 1.01 (0.80-1.28) / 0.92
Green 2006 / CC / British Caucasian / DSM-IV / 962/2100 / 0.81 / 1.06 (0.92-1.22) / 0.39
Muller 2006† / FAM / Canadian / DSM-IV / 312 / 0.77 / 1.63 (1.21-2.19) / 0.001
WTCCC 2007** / CC / British / RDC / 1866/2932 / 0.80 / 1.11 (0.97-1.19) / 0.17
Sklar 2008 / CC / American+British / DSM-IV+RDC / 1461/2008 / 0.83 / 0.97 (0.85-1.10) / 0.61
Asian:
Nakata 2003 / CC / Japanese / DSM-IV / 130/190 / 0.58 / 1.02 (0.74-1.41) / 0.94
Kunugi 2004 / CC / Japanese / DSM-IV / 519/588 / 0.60 / 0.98 (0.83-1.16) / 0.83
Hong 2004 / CC / Chinese / DSM-IV / 108/392 / 0.52 / 1.12 (0.83-1.52) / 0.49
Tang 2008 / CC / Chinese / DSM-IV / 197/208 / 0.56 / 1.18 (0.88-1.56) / 0.285
Other:
Kremeyer 2006 / FAM / Columbian / DIGS / 212 / 0.70 / 1.40 (0.79-2.49) / 0.001

* Overlapping samples obtained from the NIMH Bipolar Disorder Genetics Consortium.

** Partly overlapping sample with Green et al. 2006 and Neves-Pereira et al. 2005.

† Same patient sample reported by Neves-Pereira et al. 2002, from which the Val66Met allele frequency was obtained.

a CC = population-based case-control study; FAM = family-based study.

b RDC = Research Diagnostic Criteria (Spitzer et al. 1978); DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, 4th edition (American Psychiatric Association 1994); DIGS = Diagnostic Interview for Genetic Studies (Nurnberger et al. 1994).

c Frequency of the ancestral Val allele calculated from controls (for CC studies) or parents (for FAM studies).

d Pooled odds ratios and 95% confidence intervals for the Val allele versus the Met allele calculated from data reported in each study according to the DerSimonian-Laird random-effects model (DerSimonian and Laird 1986; Mantel and Haenszel 1959).

e Two-tailed P values reported in each study.

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