Evidence of sexual dimorphism of HTR1B gene on major adult ADHD comorbidities

The Association between 5-Hydroxytryptamine Receptor 1B rs13212041 Polymorphism and Trait Anxiety in Chinese Han College Subjects

Trait anxiety is a vulnerable personality factor for anxiety and depression. High levels of trait anxiety confer an elevated risk for the development of anxiety and other psychiatric disorders. There is evidence that 5-hydroxytryptamine receptor 1B (5-HT1B) gene polymorphisms play an important role in emotional disorders. Genotyping for four single-nucleotide polymorphisms (SNP) (rs11568817, rs130058, rs6297, and rs13212041) was conducted for 388 high trait anxious (HTA) individuals and 463 low traitanxious (LTA) individuals in Chinese Han college subjects. The results showed that the frequencies of the C-allele and TC + CC genotype of rs13212041 in the LTA individuals were higher than that in the HTA individuals (p = 0.025 and p = 0.014, respectively). Both the C-allele and TC + CC genotype were associated with trait anxiety decreasing (OR = 0.771 and OR = 0.71, respectively). Furthermore, different gene model analysis also showed that the C allele was a protective factor for trait anxiety in Chinese Han college subjects. These findings suggest that 5-HT1B rs13212014 may play a role in trait anxiety among China Han college subjects. The rs13212014 polymorphism may be involved in decreasing the risk of trait anxiety. These results also provide a novel insight into the molecular mechanism underlying trait anxiety.

Functional polymorphisms and transcriptional analysis in the 5' region of the human serotonin receptor 1B gene (HTR1B) and their associations with psychiatric disorders

BACKGROUND

The 5-hydroxytryptamine 1B receptor (5-HT1B) plays an essential role in the serotonin (5-HT) system and is widely involved in a variety of brain activities. HTR1B is the gene encoding 5-HT1B. Genome-wide association studies have shown that HTR1B polymorphisms are closely related to multiple mental and behavioral disorders; however, the functional mechanisms underlying these associations are unknown. This study investigated the effect of several HTR1B haplotypes on regulation of gene expression in vitro and the functional sequences in the 5' regulatory region of HTR1B to determine their potential association with mental and behavioral disorders.

METHODS

Six haplotypes consisting of rs4140535, rs1778258, rs17273700, rs1228814, rs11568817, and rs130058 and several truncated fragments of the 5' regulatory region of HTR1B were transfected into SK-N-SH and HEK-293 cells. The relative fluorescence intensities of the different haplotypes and truncated fragments were detected using a dual-luciferase reporter assay system.

RESULTS

Compared to the major haplotype T-G-T-C-T-A, the relative fluorescence intensities of haplotypes C-A-T-C-T-A, C-G-T-C-T-A, C-G-C-A-G-T, and C-G-T-A-T-A were significantly lower, and that of haplotype C-G-C-A-G-A was significantly higher. Furthermore, the effects of the rs4140535T allele, the rs17273700C-rs11568817G linkage combination, and the rs1228814A allele made their relative fluorescence intensities significantly higher than their counterparts at each locus. Conversely, the rs1778258A and rs130058T alleles decreased the relative fluorescence intensities. In addition, we found that regions from - 1587 to - 1371 bp (TSS, + 1), - 1149 to - 894 bp, - 39 to + 130 bp, + 130 to + 341 bp, and + 341 to + 505 bp upregulated gene expression. In contrast, regions - 603 to - 316 bp and + 130 to + 341 bp downregulated gene expression. Region + 341 to + 505 bp played a decisive role in gene transcription.

CONCLUSIONS

HTR1B 5' regulatory region polymorphisms have regulatory effects on gene expression and potential correlate with several pathology and physiology conditions. This study suggests that a crucial sequence for transcription is located in region + 341 ~ + 505 bp. Regions - 1587 to - 1371 bp, - 1149 to - 894 bp, - 603 to - 316 bp, - 39 to + 130 bp, and + 130 to + 341 bp contain functional sequences that can promote or suppress the HTR1B gene expression.

Machine learning classification of ADHD and HC by multimodal serotonergic data

Serotonin neurotransmission may impact the etiology and pathology of attention-deficit and hyperactivity disorder (ADHD), partly mediated through single nucleotide polymorphisms (SNPs). We propose a multivariate, genetic and positron emission tomography (PET) imaging classification model for ADHD and healthy controls (HC). Sixteen patients with ADHD and 22 HC were scanned by PET to measure serotonin transporter (SERT') binding potential with [¹¹C]DASB. All subjects were genotyped for thirty SNPs within the HTR1A, HTR1B, HTR2A and TPH2 genes. Cortical and subcortical regions of interest (ROI) were defined and random forest (RF) machine learning was used for feature selection and classification in a five-fold cross-validation model with ten repeats. Variable selection highlighted the ROI posterior cingulate gyrus, cuneus, precuneus, pre-, para- and postcentral gyri as well as the SNPs HTR2A rs1328684 and rs6311 and HTR1B rs130058 as most discriminative between ADHD and HC status. The mean accuracy for the validation sets across repeats was 0.82 (±0.09) with balanced sensitivity and specificity of 0.75 and 0.86, respectively. With a prediction accuracy above 0.8, the findings underlying the proposed model advocate the relevance of the SERT as well as the HTR1B and HTR2A genes in ADHD and hint towards disease-specific effects. Regarding the high rates of comorbidities and difficult differential diagnosis especially for ADHD, a reliable computer-aided diagnostic tool for disorders anchored in the serotonergic system will support clinical decisions.

Efficacy of Nonpharmacological Treatments on Comorbid Internalizing Symptoms of Adults With Attention-Deficit/Hyperactivity Disorder: A Meta-Analytic Review

Background: Attention-deficit/hyperactivity disorder (ADHD) is highly comorbid in adulthood. This meta-analysis was aimed at ascertaining the efficacy of different psychotherapies in improving comorbid internalizing symptoms in adults with ADHD. Method: Twenty randomized controlled trials and 12 uncontrolled pretest-posttest studies were included and combined using the inverse variance method. Risk of bias and heterogeneity assessment and moderator analyses were performed. Results: Cognitive-behavioral therapy (CBT) improved quality of life (QoL), emotional dysregulation (ED), depression, and anxiety symptoms, particularly at follow-up, which was predicted by core symptoms reduction. A significant between-group effect was obtained only on QoL, ED, and self-esteem for dialectical behavior therapy (DBT), mindfulness-based therapies (MBTs), and neurofeedback, respectively. Conclusion: Results support CBT efficacy for treating comorbid internalizing symptoms. More research is needed to determine the effectiveness of DBT, MBT, and neurofeedback. The small number of studies evaluating some therapies and the high risk of bias observed might limit these results.

Diagnosis and treatment of patients with comorbid substance use disorder and adult attention-deficit and hyperactivity disorder: a review of recent publications

PURPOSE OF REVIEW

Attention-deficit and hyperactivity disorder (ADHD) often presents with comorbid substance use disorders (SUD). Due to similarities in key symptoms of both disorders and suboptimal efficacy of the available treatments, clinicians are faced with difficulties in the diagnosis and treatment of these patients with both disorders. This review addresses recent publications between 2017 and 2019 on the etiology, prevalence, diagnosis and treatment of co-occurring ADHD and SUD.

RECENT FINDINGS

ADHD is diagnosed in 15-20% of SUD patients, mostly as ADHD with combined (hyperactive/inattentive) presentation. Even during active substance use, screening with the Adult ADHD Self-Report Scale (ASRS) is useful to address whether further diagnostic evaluation is needed. After SUD treatment, the diagnosis of ADHD generally remains stable, but ADHD subtype presentations are not. Some evidence supports pharmacological treatment with long-acting stimulants in higher than usual dosages. Studies on psychological treatment remain scarce, but there are some promising findings on integrated cognitive behaviour therapy.

SUMMARY

Diagnosis and treatment of patients with comorbid ADHD and SUD remain challenging. As ADHD presentations can change during active treatment, an active follow-up is warranted to provide treatment to the individuals' personal strengths and weaknesses.

The data on the relationship between polymorphism of HTR1B and DBH genes and attention-deficit hyperactivity disorder in adults with or without substance use disorders

There is a positive relationship between attention-deficit hyperactivity disorder and tendency toward drug use in numerous studies. The present study was aimed to investigate the relationship between polymorphism of serotonin receptor 1B gene (HTR1B) and Dopamine beta-hydroxylase gene (DBH) with attention-deficit hyperactivity disorder in adults with or without substance use disorders. In the present case-control study, as many as 355 individuals entered the present study and was categorized in different groups: control healthy group, substance use disorders group, and attention-deficit hyperactivity disorder group. For confirming attention-deficit hyperactivity disorder in adults, demographic and Conners forms were used. Moreover, SCID-I questionnaire was used to confirm or reject the individual׳s suffering from substance use disorders and other psychiatric diseases. The polymorphism of abovementioned genes was conducted by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). In case of DBH gene-Rs2519152, the findings indicated that TT, TC, and CC genotypes and T and C alleles are not different in the attention-deficit hyperactivity disorder group, substance use disorder group, the group with patients suffering from both disorders, and control group. Moreover, the frequency of TT, TA, and AA genotypes as well as T and A alleles was same in the attention-deficit hyperactivity disorder group, substance use disorder group, the group with patients suffering from both disorders, and control group.