According to genetic population studies, there are differences in the frequency of different alleles of so-called ADHD genes (or "migration genes"), such as the DRD4 allele, depending on how long people have migrated in the historic past (see e.g. Chen et al, 1999: Population Migration and the Variation of Dopamine D4 Receptor (DRD4) Allele Frequencies Around the Globe). It seems like alleles, which alter the regulation of dopamine and other neurotransmitters in such way that the carrier has a tendency towards novelty-seeking and hyperactivity, tend to be more common in migrating populations than in sedentary populations. This sounds logic and not very surprising. But what about modern migration patterns and gene alleles?

The reason for my questions is that, although a large part of the occurrence of social problems and criminality (and other norm-breaking behaviour) in immigrant populations in e.g. Sweden can be explained by socio-economic factors, also after correction for such factors there is a higher incidence of violence, crime and social problems in immigrant populations than in more sedentary populations. ADHD is a known risk factor for impulsive and norm-breaking behaviour (at least if the behavioural needs of persons with ADHD are not met by the society). So I am curious about if there might be genetic differences which might need childhood/school interventions in order to give better chances for success in life for individuals, as well as a generally more stable and safe situation for all inhabitants in socially vulnerable areas.

As far as I have understood, there are several possible interventions those might be useful to counteract norm-breaking behaviour among childdren, and thus prevent such behaviour among adolescents and adults. But with very limited resources, we need to identify both which kinds of interventions would be most cost-efficient, and also in which schools and for which groups and individuals it would give the best long-term rewarding effect to make interventions.

I realize that this issue might be politically sensitive – but it has nothing to do with races or ethnicity, rather with genetic variations between populations with different migratory patterns – that is, if the migratory behaviour itself (not ethnicity) is influenced by genes, or only by outer factors such as wars, famine, economic problems or political situations. Are people who take the chance to move away genetically similar to people who stay, or are there differences, with respect to gene alleles commonly associated with ADHD? And if there are genetic differences, could this explain parts of the differences in norm-breaking behaviour not explained by socio-economic factors between immigrants and sedentary residents in Western industrialized countries?

Question 1: Is there a genetic difference in so-called ADHD allele frequencies (e.g. DRD4) in immigrants/refugees (e.g. first or second generation) in Western industrialised countries, compared to the populations still remaining in the countries of origin, as well as the long-term sedentary populations in the current countries of residence?

Question 2: Do immigrant populations (e.g. first or second generation) in Western industrialised countries have a higher occurrence of ADHD symptoms than the general sedentary populations in the countries of origin, as well as sedentary populations in the new countries of residence?

Question 3: Which scientifically supported methods for early interventions might be suitable to use in preschools and schools to improve academic and social life success for children with ADHD tendencies and/or ADHD alleles?

Question 4: Which scientifically supported methods (which might differ from those in question 3) for early interventions might be suitable to use in preschools and schools to improve academic and social life success for children in socially vulnerable areas with a high proportion of immigrants?