Currently, peripheral COMT inhibitors have an important role in the treatment of Parkinson's disease, and central COMT inhibitors have a potential role in the treatment of various neuropsychiatric disorders, such as attention deficit hyperactivity disorder.
We examined bidirectional relations between attention-deficit/hyperactivity disorder (ADHD) symptoms and family and school climate, and the possible role of DRD4 and/or 5-HTTLPR genotypes herein.
Thus, our findings may help to improve the understanding of the neuroanatomic basis for the relationship between the COMT genotype and ADHD pathogenesis.
<b>Conclusions:</b> Prefrontal gyrification is reduced in children with ADHD who also carry the DRD4 7R allele, and it relates to critical functional skills in the executive domain in carriers of the risk allele.
The present findings indicate that the interaction between methylation of CpG7 of DRD4 and prenatal maternal stress may be predictive of the treatment response to MPH in youth with ADHD.
This study aimed to investigate the effects of regulation of the dopamine D4 receptor (DRD4) on functional brain activity during the resting state in ADHD children using the methods of regional homogeneity (ReHo) and functional connectivity (FC).
We examined 4 SNPs located on genes previously associated to dyslexia (KIAA0319, DCDC2, DYX1C1 and FOXP2) and 3 SNPs within genes related to ADHD (COMT, MAOA and DBH) in a cohort of Spanish children (N = 2078) that met the criteria of having one, both or none of these disorders (dyslexia and ADHD).
An association between the presence of the long allele of the DRD4 gene polymorphism and ADHD-like failure in CPT performance was evident in the non-affected parents of adolescents with ADHD in childhood.
After adjustment for other covariates, children who carried the DRD4 GG genotype, had been exposed to high DMP levels (more than the median), and had high HNE-MA levels had a significantly increased risk for developing ADHD (OR = 11.74, 95% CI: 2.12-65.04).
After adjustment for other covariates, children who carried the DRD4 GG genotype, had been exposed to high DMP levels (more than the median), and had high HNE-MA levels had a significantly increased risk for developing ADHD (OR = 11.74, 95% CI: 2.12-65.04).
This endorses the general thesis that DRD4 exon 3 VNTR polymorphism is related to ADHD, despite that the exact length or number of repeats of the associated alleles varies across ethnicity.
For CpG sites at genes of the dopaminergic (COMT, ANKK1) and the neurotrophic (BDNF, NGFR) system, associations with the Nogo-P3 as well as ADHD symptom severity were found suggesting that these systems are involved in response control deficits in ADHD.
Given that prenatal exposure to alcohol or smoking is known to affect dopamine-rich brain regions, we hypothesized that individuals carrying the ADHD risk alleles of the dopamine receptor D4 (<i>DRD4</i>) and dopamine transporter (<i>DAT1</i>) genes may be especially sensitive to their effects.
To examine the association of the DNA methylation of DAT1 and DRD4 gene with methylphenidate (MPH) response in attention deficit hyperactivity disorder (ADHD).
The authors infer that the age of onset of ADHD may at least partially be affected by DRD5 variants warranting further investigation on the role of DRD5 in the disease etiology.
This study aimed to assess the role of the catechol-O-methyltransferase (<i>COMT</i>) and of the dopamine transporter (<i>DAT1</i>) genes on ADHD symptoms in the general population.
In a large observational ADHD cohort study (N = 316), the effects of cumulative stimulant treatment, genotype (for DAT1 haplotype and DRD4 variants), and treatment-by-genotype interactions on striatal, frontal, and hippocampal volumes and their interactions with age were evaluated.
We tested associations between ADHD symptoms and epigenetic changes to the DRD4 gene in DNA extracted from blood and saliva in N = 330 children referred for a variety of behavioural and emotional problems.