Both the 120-bp TR and rs1800955 are reportedly related to the risk of schizophrenia onset, and a meta-analysis positively supported the results for the variants described herein.5 Located in the promoter region of the DRD4 gene, these variants appear in different haplotype blocks.10 In addition, the longer allele of the 120-bp TR and the T allele on rs1800955 decrease the DRD4 messenger RNA (mRNA) expression,11,12 so these variants are regarded to be genetically functional. Here, DRD4 is linked to schizophrenia.