Dopamine Receptor Gene D4 Polymorphisms and Early Sexual Onset: Gender and Environmental Moderation in a Sample of African-American Youth

Abstract

Purpose Early sexual onset and its consequences disproportionately affect African American youth, particularly male youth. The dopamine receptor D4 gene, DRD4, has been linked to sexual activity and other forms of appetitive behavior, particularly for male youth and in combination with environmental factors [gene × environment (G × E) effects]. The differential susceptibility perspective suggests that DRD4 may exert this effect by amplifying the effects of both positive and negative environments. We hypothesized that DRD4 status would amplify the influence of both positive and negative neighborhood environments on early sexual onset among male, but not female, African Americans. Methods Hypotheses were tested with self-report, biospecimen, and census data from 5 prospective studies of male and female African American youth in rural Georgia communities, N = 1677. Early sexual onset was defined as intercourse before age 14. Results No significant G × E findings emerged for female youth. Male youth with a DRD4-long allele were more likely than those with 2 DRD4-short alleles to report early sexual onset in negative community environments and not to report early onset in positive community environments. Conclusions Dopaminergic regulation of adolescent sexual behaviors may operate differently by gender. DRD4 operated as an environmental amplification, rather than a vulnerability, factor.

The Construction of Big Data Computational Intelligence System for E-Government in Cloud Computing Environment and Its Development Impact

“…Deeper mining and organization of data can help people obtain data products. "Big data strategy" is also on the agenda with the widespread use of big data [3]. Big data technology can be used to collect, process, and handle large amounts of data and analyze them from a professional perspective.…”

Paraphilic Sexual Offenders Do Not Differ from Control Subjects with Respect to Dopamine- and Serotonin-Related Genetic Polymorphisms

“…Therefore, for this study, genetic polymorphisms previously associated with behavioral control, addictive behaviors, and sexual functions were chosen. Specifically, the dopamine type 1 receptor gene (DRD1) has been associated with reward deficiency, substance abuse risk, 21 and age at first sexual intercourse 22 ; the dopamine type 2 receptor gene (DRD2) has been related to novelty seeking, behavioral control, and sexual dysfunction in male schizophrenia 23 ; the dopamine type 4 receptor gene (DRD4) has been associated with impulsivity, 24 age at sexual initiation, 25 and desire, arousal, and sexual function 26 ; the serotonin type 2A receptor gene (5HTR2A) has been associated with behavioral impulsivity 27 and human "loving style" 28 ; the dopamine transporter gene (DAT) has been related to behavioral control 24 and premature ejaculation 29 ; the serotonin transporter gene (SLC6A4) has been associated with behavioral control, number of sexual partners, 30 and susceptibility to premature ejaculation 31 ; the catechol-O-methyltransferase gene (COMT; a DA-metabolizing enzyme) has been associated with behavioral control and male sexual orientation 32 ; the tryptophan hydroxylase 2 gene (TPH2; an enzyme in 5-HT synthesis) has been related to impulsivity 33 and sexual preference in an animal model 18 ; the monoamine oxidase A gene (MAOA) has been associated with impulsivity, attempted rape, and exhibitionism 15 ; and the brain-derived neurotrophic factor gene (BDNF; BDNF is a neurotrophin involved in the development and survival of neurons and in modulating the activity of neurotransmitter systems, particularly 5-HT and DA) has been associated with behavioral control and sexual desire during treatment for depression. 34 We hypothesized that there would be significant differences in the distribution of alleles and genotypes in these polymorphisms between paraphilic sexual offenders and controls.…”