Four GRIN2A variants (rs1070487, rs6497730, rs4587976, and rs1650420), all located at a 32 kb area of intron 3 (5' to the translation site at exon 3), accounted for some of the strongest signals in the association test (P = 0.0006-0.0039, Tables 1 and 2). Two additional SNPS from the same block (rs1071502 and rs1366076) gave nominal significant P values for association (P < 0.05) but did not pass the threshold value. Eleven additional GRIN2A SNPs gave negative results. The LD map and haplotype block structure of this region are shown on Fig. 1e; SNPs rs1070487 and rs6497730, are in strong LD (D' = 0.88). SNP rs4587976 forms a 7 kb block with SNPs rs1071502 and rs1366076. SNP rs1650420 is in complete LD (D' = 1) with rs1366076 but is not part of a block, under this block definitions. Haplotype analysis of block 1 (rs4587976-rs1071502-rs1366076) revealed significant association of haplotypes GAT (protective) and CAT (risk), (uncorrected P =9.6E-05 and 0.0036, respectively, Table 3). The association test of the GAT haplotype was close to significance after correction for multiple testing (P =
