As the previous estimate of Tourette syndrome h2g from the first Tourette GWAS (h2g LMM=0.58, SE=0.09) (7) was significantly higher than that observed in this study, additional heritability analyses were conducted in the individual datasets stratified on ascertainment status using linear mixed models (LMM)(7) (Table 2). These analyses confirmed both the high SNP-based heritability of the sib-pair enriched Tourette GWAS1 sample (h2g GWAS1-LMM=0.56, SE=0.10; p=1.2×10−9), and the lower heritability of the larger GWAS2 sample (h2g GWAS2-LMM=0.29, SE=0.04; p=5.5×10−14).
