Table 2.

Summary and meta-analysis of all published association analyses of the serotonin transporter 5-HTTLPR gain-of-function L_A allele and obsessive-compulsive disorder. Black bars in the forest plot represent 95% confidence intervals for odds ratio; the sample size is reflected in symbol size. The sample for the present report consisted of European-ancestry early-onset (< 18 years of age) probands; demographic and phenotypic characteristics for the remaining studies are as follows: Hu et al., 2006 [11] - case-control: European-ancestry individuals, early- and adult-onset probands; Hu et al., 2006 [11] - trios: predominantly European-ancestry families, early- and adult-onset probands; Wendland et al., 2007 [28] - European-ancestry individuals, early- and adult-onset probands; Tibrewal et al., 2010 [20] - Asian-ancestry individuals, early- and adult-onset probands; Voyiaziakis et al., 2011 [24] - primarily European-ancestry families, early-onset probands and at least two affected siblings per family.

Abbreviations: CC, case-control; TDT, transmission disequilibrium test; FBAT, family-based association testing; CI, confidence interval.