Introduction: When the frequency of a gene in the general population exceeds 1%, is not considered a random mutation but a mutation that has been positively selected during evolution. The high prevalence of attention deficit/hyperactivity disorder (ADHD) from 5-10% and its association with the seven-repeat allele of DRD4, which is positively selected in evolution, raising the possibility that ADHD increases the reproductive fitness of the individual and/or group. One of the main characteristics of ADHD is its diversity and is a well recognized fact that diversity confers many benefits to a population (eg. immunity).
Development: This article discusses the various studies that support this hypothesis and offers further explanations on the prevalence, age distribution and sex distribution of the severity and heterogeneity of ADHD.
Conclusion: It is possible that the presence of altered gene combinations, as in ADHD, can bring concrete benefits to society but are detrimental to the individual.