title: No association of the dopamine D4 receptor (DRD4) and -521 C/T promoter polymorphisms with infant attachment disorganization.
abstract: In a first molecular genetic study Lakatos and colleagues found an association between attachment disorganization and the dopamine D4 receptor (DRD4) gene polymorphism, in particular in the presence of the -521 T allele in the promoter region of the DRD4 gene. Replication of their study in a sample of 132 infants did not confirm the role of the DRD4 7+ -allele and the -521C/T promoter gene in disorganized attachment. Although our sample was larger, and contained more children with CT or TT alleles, which enhanced the probability of finding the DRD4 and C/T interaction, the association was not found. Even when we combined our sample with the Lakatos sample, the interaction effect of the DRD4 and -521 C/T polymorphisms on disorganized attachment was absent.
authors.affiliation: bakermans@fsw.leidenuniv.nl
authors.forename: M J
authors.initials: MJ
authors.lastname: Bakermans-Kranenburg
authors.forename: M H
authors.initials: MH
authors.lastname: Van Ijzendoorn
mesh_terms: D000483:Alleles; D002675:Child, Preschool; D017931:DNA Primers / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D009769:Object Attachment; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic; D019962:Reactive Attachment Disorder / Q000235:genetics*; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D050638:Receptors, Dopamine D4; D014427:Twins / Q000235:genetics*
chemical_list: D017931:DNA Primers; C493599:DRD4 protein, human; D017448:Receptors, Dopamine D2; D050638:Receptors, Dopamine D4