ADHD and the DRD4 exon III 7-repeat polymorphism: an international meta-analysis.
We sought to elucidate the relationship of ADHD (Attention-Deficit Hyperactivity Disorder) to the DRD4 exon III VNTR 7R allele worldwide using analytic techniques and to relate these findings to the field of cultural neuroscience. To focus on a potential moderating role of race/ethnicity, we excluded over 30 papers that have explored the relationship between the DRD4 7R and ADHD but had unclear or lax racial-ethnic inclusion criteria. The papers in this meta-analysis were only included if a single race made up 95% or more of their sample. We searched for and translated papers not published in English, and found a significant difference in the relationship of ADHD and DRD4 7R in people of European-Caucasian (Odds ratio 1.635, Z = 3.936, P < 0.00001) and South American (Odds ratio 2.407, Z = 3.317, P = 0.001) descent vs people of Middle Eastern ancestry (Odds ratio 0.717, Z = -2.466; P = 0.014). We also examined the moderating effect of differing ADHD diagnoses, subject recruitment, control recruitment and male to female ratio. Finally, we consider the implications of these data for cultural neuroscience.
Nikolaidis
Aki
A
Department of Psychology, Yale University, New Haven, CT, USA. gaki775@gmail.com
Gray
Jeremy R
JR
D000483:Alleles; D000818:Animals; D044466:Asian People; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000235:genetics* / Q000523:psychology; D002648:Child; D005091:Exons / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D006801:Humans; D007802:Language; D008297:Male; D008877:Middle East; D018579:Patient Selection; D050638:Receptors, Dopamine D4 / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D018570:Risk Assessment; D012727:Sex Characteristics; D013020:South America; D044465:White People
C493599:DRD4 protein, human; D050638:Receptors, Dopamine D4