Impacts of interactions between ADH1B and ALDH2 genotypes on alcohol flushing, alcohol reeking on the day after drinking, and age distribution in Japanese alcohol-dependent men

Associations of ADH1B and ALDH2 genotypes and alcohol flushing with drinking history, withdrawal symptoms, and ICD-10 criteria in Japanese alcohol-dependent men

OBJECTIVES

Given the high prevalence of fast-metabolizing alcohol dehydrogenase-1B*2 (ADH1B*2 ) and inactive aldehyde dehydrogenase-2*2 (ALDH2*2 ) alleles in East Asians, we evaluated how the ADH1B / ALDH2 genotypes and alcohol flushing might affect the development of alcohol dependence (AD).

METHODS

We evaluated how the ADH1B / ALDH2 genotypes and self-reported alcohol flushing affected history of drinking events and withdrawal symptoms and ICD-10 criteria in 4116 Japanese AD men.

RESULTS

The ADH1B*1/*1 group and ALDH2*1/*1 group were 1-5 years younger than the ADH1B*2 (+) and ALDH2*1/*2 groups, respectively, for all of the ages at onset of habitual drinking, blackouts, daytime drinking, uncontrolled drinking, withdrawal symptoms, and first treatment for AD, and the current age. Blackouts were more common in the ADH1B*1/*1 group and ALDH2*1/*1 group. Daytime drinking, uncontrolled drinking, and withdrawal symptoms, such as hand tremor, sweating, convulsions, and delirium tremens/hallucinations were more common in the ADH1B*1/*1 group. The ADH1B*1/*1 was positively associated with the ICD-10 criteria for 'tolerance' and 'withdrawal symptoms'. The ADH1B*1/*1 group and ALDH2*1/*2 group had a larger ICD-10 score. Never flushing was reported by 91.7% and 35.2% of the ALDH2*1/*1 and ALDH2*1/*2 carriers, respectively. After a 1-2-year delay in the onset of habitual drinking in the former-/current-flushing group, no differences in the ages of the aforementioned drinking milestones were found according to the flushing status.

CONCLUSION

The ADH1B*1/*1 and ALDH2*1/*1 accelerated the development of drinking events and withdrawal symptoms in Japanese AD patients. ICD-10 score was larger in the ADH1B*1/*1 group and ALDH2*1/*2 group. The effects of alcohol flushing on drinking events were limited.

Association between alcohol dehydrogenase polymorphisms (rs1229984, rs1573496, rs1154460, and rs284787) and susceptibility to head and neck cancers: A systematic review and meta-analysis

OBJECTIVE

Head and neck cancer (HNC) is a prevalent and complex group of malignancies with increasing incidence globally. Alcohol dehydrogenases (ADHs) play a crucial role in alcohol metabolism, and their polymorphisms have been linked to HNC risk. This systematic review and meta-analysis aims to evaluate the association between ADH polymorphisms and susceptibility to HNCs, incorporating additional analyses and adding more studies to increase power and accuracy of the results.

DESIGN

Subgroup analysis, meta-regression analysis, and sensitivity analyses were conducted to explore potential differences within the data and assess the stability of pooled odds ratios (ORs). To mitigate the risk of false conclusions from meta-analyses, a trial sequential analysis was performed.

RESULTS

For ADH1B rs1229984, the pooled OR (95 % confidence interval (CI)) was 0.73 (0.65, 0.82), 0.42 (0.35, 0.50), 0.57 (0.44, 0.73), 0.56 (0.50, 0.62), and 0.80 (0.73, 0.88), as well as for ADH7 rs1573496, the pooled OR was 0.72 (0.62, 0.85), 0.36 (0.17, 0.74), 0.76 (0.64, 0.91), 0.80 (0.71, 0.91), and 0.38 (0.18, 0.78) with a p < 0.05 in all allelic, homozygous, heterozygous, recessive, and dominant models, respectively. However, no significant association was found between the ADH7 rs1154460 and rs284787 polymorphisms and the risk of HNC with pooled ORs of 1.11 (p = 0.19) and 1.09 (p = 0.24) for the recessive model, respectively. The ethnicities, tumor subsites, control sources, sample sizes, quality scores, and Hardy-Weinberg equilibrium statuses were confounding factors.

CONCLUSION

The ADH1B rs1229984 and ADH7 rs1573496 polymorphisms are significantly associated with a reduced risk of HNC.

Impacts of ADH1B rs1229984 and ALDH2 rs671 polymorphisms on risks of alcohol-related disorder and cancer

BACKGROUND

ADH1B rs1229984 and ALDH2 rs671 are the specifically prevalent functional variants in the East Asians. These variants, which result in a dramatic change in enzyme activity, are highly associated with alcohol-related disorders and cancer. Previous studies focusing on the additive and synergic effects of the variants are few and inconsistent. The aim of the research was to evaluate the associations of ADH1B rs1229984 and ALDH2 rs671 with the risks of alcohol-related disorder and cancer.

METHODS

This cohort study enrolled 42,665 participants from the Taiwan Precision Medicine Initiative database, including 19,522 and 20,534, ADH1B and ALDH2 carriers, respectively. The associations between the two variants and cancer risk were analyzed by univariable and multivariable logistic regression.

RESULTS

Compared with the noncarriers, the ADH1B rs1229984 variant had a stronger effect on alcohol-related disorders and was related to an increased risk of alcohol-related cancers. The CC genotype of ADH1B rs1229984 was significantly associated with cancer of the larynx, pharynx, and nasal cavities [odds ratio (OR) = 1.56, p = 0.0009], cancer of the pancreas (OR = 1.66, p = 0.018), and cancer of the esophagus (OR = 4.10, p < 0.001). Participants who carried the rs1229984 TC/CC and rs671 GG genotypes were at higher risk of esophageal cancer (OR = 3.02, p < 0.001). The risk of esophageal cancer was increased by 381% (OR = 4.81, p < 0.001) in those carrying the rs1229984 TC/CC and rs671 GA/AA genotypes.

CONCLUSION

rs1229984 and rs671 are common and functionally important genetic variants in the Taiwanese population. Our findings provide strong evidence of additive and synergic risks of ADH1B and ALDH2 variants for alcohol-related disorders and cancer. The results suggested that are reduction in alcohol consumption should be advised as a preventive measure for high-risk patients carrying ADH1B rs1229984 C or the ALDH2 rs671 A allele.

Exploring the Role of Alcohol Metabolizing Genotypes in a 12-Week Clinical Trial of Naltrexone for Alcohol Use Disorder

Background: The efficacy of naltrexone in the treatment of alcohol use disorder (AUD) has been associated with a set of variables not directly related with the expression of opioid receptors. All the variables have been found to be highly associated with AUD itself or more severe clinical levels of AUD. Objectives: Given the high association between alcohol metabolizing enzymes (AME) and the outcome of AUD, the present study aims to investigate the role of AME genotype variants in the treatment of AUD with naltrexone. Methods: We carried out a 12-week longitudinal clinical trial based on the treatment of AUD patients with naltrexone (N = 101), stratified by different alcohol metabolization genotypes. Genotyping was performed after the inclusion of the patients in the study, based on the individual presence of single nucleotide polymorphisms (SNPs) in the ADH (alcohol dehydrogenase)1B (ADH1B*2 and ADH1B*3), ADH1C (ADHC*1) and ALDH (aldehyde dehydrogenase) 2 (ALDH2*2) genes. The outcome of alcohol use has been monitored employing the timeline follow-back during the treatment. Results: The ADH1C*1 (Ile350Val, rs698) and ALDH2*2 (Glu504Lys, rs671) polymorphisms were associated with a better response to naltrexone treatment, whereas the ADH1B*3 (Arg370Cys, rs2066702) allelic variant showed a negative outcome. Conclusions: The present study explores a genomic setting for the treatment of AUD with naltrexone. According to our findings, the association between ADH1C*1 and ALDH2*2 variants and better outcomes suggests a successful treatment, whereas the ADH1B*3 mutated allele might lead to an unsuccessful treatment. Further studies should be performed to investigate the relationship between alcohol metabolizing genotypes, the family history of alcohol use disorders and the effect of naltrexone on the outcomes. Genotyping may be a valuable tool for precision-medicine and individualized approach, especially in the context of alcohol use disorders. The small number of subjects was the main limitation of the present study.

Combinations of alcohol-induced flushing with genetic polymorphisms of alcohol and aldehyde dehydrogenases and the risk of alcohol dependence in Japanese men and women

OBJECTIVE

The risk of alcohol dependence (AD) in Japanese men and women was evaluated according to combinations of alcohol flushing and aldehyde dehydrogenase-2 (ALDH2, rs671) and alcohol dehydrogenase-1B (ADH1B, rs1229984) genotypes, all of which are known to determine AD susceptibility in Asians. Previous studies have focused on men, since women account for a smaller proportion of AD subjects.

METHODS

Case control studies were conducted between 3721 male and 335 female AD Japanese and 610 male and 406 female controls who were asked about their current or former tendency to experience facial flushing after drinking a glass of beer and underwent ALDH2 and ADH1B genotyping. The time at which alcohol-induced facial flushing tendencies had disappeared in former-flushing AD subjects was also evaluated.

RESULTS

Current alcohol flushing, the inactive ALDH2*1/*2 genotype, and the fast-metabolizing ADH1B*2 allele were less frequently found in the AD groups. Although alcohol flushing was strongly influenced by the ALDH2 and ADH1B genotypes, multiple logistic model showed that never or former flushing and the genotype combinations were independent strong risk factors of AD in men and women. Never or former flushing (vs. current flushing) markedly increased the odds ratios of AD in carriers of each of the ALDH2 and ADH1B genotype combinations. The temporal profiles for drinking and flushing in former-flushing AD subjects revealed that the flushing response disappeared soon after or before the start of habitual drinking during young adulthood, regardless of the ALDH2 genotype.

CONCLUSION

Although alcohol flushing is influenced by the ALDH2 and ADH1B genotypes, constitutional or acquired flushing tolerance is an independent susceptibility trait for AD. The combination of the alcohol flushing status and the ALDH2 and ADH1B genotypes can provide a better new strategy for AD risk assessment than the alcohol flushing status alone or the genotypes alone in Asian men and women.

Whole Genome Interpretation for a Family of Five

Although best practices have emerged on how to analyse and interpret personal genomes, the utility of whole genome screening remains underdeveloped. A large amount of information can be gathered from various types of analyses via whole genome sequencing including pathogenicity screening, genetic risk scoring, fitness, nutrition, and pharmacogenomic analysis. We recognize different levels of confidence when assessing the validity of genetic markers and apply rigorous standards for evaluation of phenotype associations. We illustrate the application of this approach on a family of five. By applying analyses of whole genomes from different methodological perspectives, we are able to build a more comprehensive picture to assist decision making in preventative healthcare and well-being management. Our interpretation and reporting outputs provide input for a clinician to develop a healthcare plan for the individual, based on genetic and other healthcare data.