The DRD2 A1 allele was present in 73.9% of the obese subjects with comorbid substance use disorder compared to 23.5% in obese subjects without comorbid substance use disorder.
The identification of phenotypes of DRD2 genotypes suggests that the observed intronic DRD2 mutations may have functional consequences that predispose individuals to a variety of substance use disorders.
Because the D2 dopamine receptor (DRD2) A1 allele has been associated with alcoholism and other substance use disorders, negative affect, measured by the Beck Depression Inventory (BDI), was determined in four groups of children: boys and girls with the A1+ allele (A1A1 and A1A2 genotypes) and with the A1- allele (A2A2 genotype).
A total of 110 adult patients with ASD (n=61) or ADHD (n=49) with or without a lifetime history of SUD participated in a study in which we genotyped polymorphisms in five known candidate genes for (one of) the disorders, i.e. the 5HTTLPR in SLC6A4/5-HTT, rs1800497 (TaqIA C>T) in DRD2, rs7794745 in CNTNAP2, rs1843809 in TPH2, and rs6565113 in CDH13.
In the presented study, one of selected polymorphisms of DRD2 gene, revealed to be correlated with substance use disorder (at the limit of statistical significance), which could suggest its impact on dependence endophenotype.
Imaging gene-substance interactions: the effect of the DRD2 TaqIA polymorphism and the dopamine agonist bromocriptine on the brain activation during the anticipation of reward.
We hypothesize that dopamine D2 receptor (DRD2) gene Taq1 A2 allele is associated with a subtype of non-SUD schizophrenics and as such may act as a putative protective agent against the development of addiction to alcohol or other drugs of abuse.
However, a meta-analysis of a large number of Caucasian alcoholics (both more severe and less severe) and controls (both assessed and unassessed for substance use disorders) revealed a significantly higher frequency (p < 10(-6)) and prevalence (p < 10(-8)) of the DRD2 A1 allele in the alcoholics.
Analysis of the available data suggests that the DRD2 variants represent one of the most prominent single-gene determinants of susceptibility to severe alcoholism and other substance use disorders.
Furthermore, sib pair analysis incorporating information across all three sib pair categories: concordant affected, discordant and concordant unaffected revealed no effect of DRD2 genotype or haplotype on alcoholism or substance use disorder.
If music causes a powerful activation in spite of the DRD2 A1 allele due to a strong DA neuronal release which subsequently impinges on existing D2 receptors, then it is reasonable to assume that music is a strong indirect D2 agonist (by virtue of DA neuronal release in the NAc) and may have important therapeutic applicability in Reward Deficiency Syndrome (RDS) related behaviors including Substance Use Disorder (SUD).Ross et al.
SUD and NSUD disorders were diagnosed according to the fourth edition of the Diagnostic and Statistical Manual of Mental Health Disorders criteria using the Psychiatric Research Interview for Substance and Mental Disorders.Incidence Rates (IR) are presented.The 5-HTTLPR polymorphism was analyzed.Hardy-Weinberg equilibrium was studied.
Childhood adversities and the 5-HTTLPR polymorphism are involved in the aetiology of substance use disorders though findings exploring the existence of a gene-environment interaction were inconclusive.
Serotonin transporter promoter polymorphism (5-HTTLPR) genotype was previously found associated with substance use disorders, particularly in the subjects with comorbid antisocial behavior, and with temperament and personality traits at risk for substance abuse.
Using the genotype data of 55 studies (7999 cases, 8264 controls, and 676 families or parent-offspring trios) published in the past 15 years, we have conducted comprehensive meta-analyses to examine the associations of the 5-HTTLPR and STin2 polymorphisms with substance use disorder.
We found three candidate genes associated with both BD and TUD (COMT, SLC6A3, and SLC6A4) and commonality analysis suggests that these genes interact in predisposing psychiatric and substance use disorders.
A total of 110 adult patients with ASD (n=61) or ADHD (n=49) with or without a lifetime history of SUD participated in a study in which we genotyped polymorphisms in five known candidate genes for (one of) the disorders, i.e. the 5HTTLPR in SLC6A4/5-HTT, rs1800497 (TaqIA C>T) in DRD2, rs7794745 in CNTNAP2, rs1843809 in TPH2, and rs6565113 in CDH13.
Our data suggest that a decreased expression of the gene encoding the 5-HTT transporter, due to "S" promoter polymorphism, may be associated with an increased risk for substance use disorders, particularly in the subjects with more consistent aggressiveness and impulsiveness.
On the whole, our preliminary data suggest that the association between 5-HT transporter polymorphism and psycho-stimulant use may be mediated by mother-child relationship and parental attachment perception, both being environmental and genetic factors involved in the proneness to substance use disorders, particularly in aggressive-antisocial individuals.