HDAC4 and attention deficit-hyperactivity disorder: However, a simple look-up in the latest ADHD GWAS meta-analysis performed by the Psychiatric Genomics Consortium and Danish IPSYCH group51 found no evidence of association with either rs62182100 or the three SNPs in LD (rs62182145, rs62182153, and rs62182931) within HDAC4. Also, although one other study52 has recently reported cross-disorder evidence of association (p = 7.65 × 10−6) for rs3791556 located within the HDAC4 gene and five major psychiatric disorders (including ADHD) the associated SNP (rs3791556) is not in LD with the SNP associated with IIRTV in this study.