These significant variants include the following genes HCRTR1, GAD1, HDAC3 and FKBP5, earlier associated with neuropsychiatric diseases.32 Interestingly, the GAD1 SNP rs2241165 is in perfect LD with rs2270335, which has been previously linked with grey matter loss in childhood-onset schizophrenia.33 Moreover, we extended our analyses on the relationship of the methylation levels with gene expression, identifying associations with GAD1 and COMT expression. This evidence concerns the gene COMT and Rare pervasive developmental disorder.