Omdat ik een n.e.r.d. ben en het toch even wilde opzoeken, ik vond dit:
Association study of a dopamine transporter polymorphism and attention deficit hyperactivity disorder in UK and Turkish samples, 2001
Molecular genetic studies in attention deficit hyperactivity disorder (ADHD) have focused on candidate genes within the dopamine system, which is thought to be the main site of action of stimulant drugs, the primary pharmacological treatment of the disorder. Of particular interest are findings with the dopamine transporter gene (DAT1), since stimulant drugs interact directly with the transporter protein. To date, there have been eight published association studies of ADHD with a 480 base-pair allele of a variable number tandem repeat (VNTR) polymorphism in the 3'-untranslated region of the gene, five that support an association and three against. We have analysed the same VNTR marker in a dataset of UK Caucasian children and an independent dataset of Turkish Caucasian children with DSM-IV ADHD, using the transmission disequilibrium test (TDT). Results from the UK, but not the Turkish sample (X²=0.93, P=0.34) support association and linkage between genetic variation at the DAT1 locus and ADHD. When considered alongside evidence from other published reports, there is only modest evidence for the association, consistent with a very small main effect for the 480-bp allele, however we find significant evidence of heterogeneity between the combined dataset. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Uit een wat ander onderzoek vind ik dit:
Although ADHD is likely to be multifactorial in its etiology and its heritability is likely to be polygenetic, the present findings suggest that polymorphic variation in the gene encoding the D4 dopamine receptor may be a contributing factor in the expression of symptoms associated with ADHD (Dopamine D4 receptor gene polymorphism is associated with attention deficit hyperactivity disorder, 1996).
Sounds like Fool is right! Maar ja, je hebt inderdaad altijd weer onderzoeken die zoiets tegenspreken en het is idd ook zo dat er veel meer factoren zijn die bijdragen aan de uiting van symptomen. Anyhow: er is iig wel bewijs voor polymorfisme van de receptoren.
